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86 ing to the numbers, no doubt, Ajax is victorious, but history hands down the name of Ulysses as the conqueror. Achilles and Hector [may be adduced as examples], Achilles, according to the rule of the number nine, makes four monads; Hector one: Achilles gains the victory. Again, Achilles and Asteropæus [are instances]. Achilles makes four monads, Asteropæus three: Achilles conquers. Again, Menelaus and Euphorbus [may be adduced as examples]. Menelaus has nine monads, Euphorbus eight: Menelaus gains the victory.

Some, however, according to the rule of the number seven, employ the vowels only, but others distinguish by themselves the vowels, and by themselves the semi-vowels, and by themselves the mutes; and, having formed three orders, they take the roots by themselves of the vowels, and by themselves of the semi-vowels, and by themselves of the mutes, and they compare each apart. Others, however, do not employ even these customary numbers, but different ones: for instance, as an example, they do not wish to allow that the letter p has as a root 8 monads, but 5, and that the [letter] x [si] has as a root four monads; and turning in every direction, they discover nothing sound. When, however, they contend about the second [letter], from each name they take away the first letter; but when they contend about the third [letter], they take away two letters of each name, and calculating the rest, compare them.

I think that there has been clearly expounded the mind of arithmeticians, who, by means of numbers and of names, suppose that they interpret life. Now I perceive that these, enjoying leisure, and being trained in calculation, have been desirous that, through the art delivered to them from childhood, they, acquiring celebrity, should be styled prophets.


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NZYQ

AND

MINISTER FOR IMMIGRATION, CITIZENSHIP AND MULTICULTURAL AFFAIRS & ANOR

The questions stated for the opinion of the Full Court in the further amended special case filed on 31 October 2023 be answered as follows:

Question 1: On their proper construction, did sections 189(1) and 196(1) of the Migration Act 1958 (Cth) authorise the detention of the plaintiff as at 30 May 2023?

Answer: Yes, subject to section 3A of the Migration Act 1958 (Cth).

Question 2: If so, are those provisions beyond the legislative power of the Commonwealth insofar as they applied to the plaintiff as at 30 May 2023?

Answer: Yes.

Question 3: On their proper construction, do sections 189(1) and 196(1) of the Migration Act 1958 (Cth) authorise the current detention of the plaintiff?

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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 Answer: Yes, subject to section 3A of the Migration Act 1958 (Cth).

Question 4: If so, are those provisions beyond the legislative power of the Commonwealth insofar as they currently apply to the plaintiff?

Answer: Yes.

Question 5: What, if any, relief should be granted to the plaintiff?

Answer: The following orders should be made:
 * 1. It is declared that, by reason of there having been and continuing to be no real prospect of the removal of the plaintiff from Australia becoming practicable in the reasonably foreseeable future:1. the plaintiff's detention was unlawful as at 30 May 2023; and

2. the plaintiff's continued detention is unlawful and has been since 30 May 2023.

2. A writ of habeas corpus issue requiring the defendants to release the plaintiff forthwith.

Question 6: Who should pay the costs of the further amended special case?

Answer: The defendants.

Representation

C L Lenehan SC and F I Gordon KC with J S Stellios and T M Wood for the plaintiff (instructed by Allens)

S P Donaghue KC, Solicitor-General of the Commonwealth, and P D Herzfeld SC with Z C Heger and A M Hammond for the defendants (instructed by Australian Government Solicitor)

P M Knowles SC with M F Caristo for the Australian Human Rights Commission, appearing as amicus curiae (instructed by Australian Human Rights Commission)


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 R C A Higgins SC with A M Hochroth, J R Murphy and K E W Bones for the Human Rights Law Centre and the Kaldor Centre for International Refugee Law, appearing as amici curiae (instructed by Human Rights Law Centre)

 * Notice: This copy of the Court's Reasons for Judgment is subject to formal revision prior to publication in the Commonwealth Law Reports.


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Rh And they, measuring the letters up [and] down, have wandered into trifling. For if they fail, they say, in putting forward the difficulty. Perhaps this name was not a family one, but imposed, as also lighting in the instance they argue in the case of [the names] Ulysses and Ajax. Who, taking occasion from this astonishing philosophy, and desirous of being styled "Heresiarch," will not be extolled?

But since, also, there is another more profound art among the all-wise speculators of the Greeks (to whom heretical individuals boast that they attach themselves as disciples, on account of their employing the opinions of these [ancient philosophers] in reference to the doctrines attempted [to be established] by themselves, as shall a little afterwards be proved); but this is an art of divination, by examination of the forehead, or rather, I should say, it is madness: yet we shall not be silent as regards this [system]. There are some who ascribe to the stars fibres that mould the ideas and dispositions of men, assigning the reason of this to births [that have taken place] under particular stars; they thus express themselves: Those who are born under Aries will be of the following kind: long head, red hair, contracted eyebrows, pointed forehead, eyes grey and lively, drawn cheeks, long-nosed, expanded nostrils, thin lips, tapering chin, wide mouth. These, he says, will partake of the following nature: cautious, subtle, perspicuous, prudent, indulgent, gentle, over-anxious, persons of secret resolves, fitted for every undertaking, pre-


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 CATCHWORDS

NZYQ v Minister for Immigration, Citizenship and Multicultural Affairs

Constitutional law (Cth) – Judicial power of Commonwealth – Immigration detention – Indefinite detention without judicial order – Where plaintiff stateless Rohingya Muslim having well-founded fear of persecution in Myanmar – Where plaintiff's bridging visa cancelled following criminal conviction – Where following release from criminal custody plaintiff taken into immigration detention under s 189 of Migration Act 1958 (Cth) ("Act") – Where plaintiff's application for protection visa refused and finally determined – Where ss 198(1) and 198(6) of Act imposed duty upon officers of Department administering Act to remove plaintiff from Australia as soon as reasonably practicable – Where s 196(1) of Act required plaintiff to be kept in immigration detention until removed from Australia, deported, or granted visa – Where attempts by Department to remove plaintiff from Australia unsuccessful as at date of hearing – Where no real prospect of removal of plaintiff from Australia becoming practicable in reasonably foreseeable future – Where plaintiff sought writ of habeas corpus requiring release from detention forthwith – Whether application for leave to reopen constitutional holding in Al-Kateb v Godwin (2004) 219 CLR 562 should be granted – Whether constitutional holding in Al-Kateb should be overruled – Whether detention of plaintiff punitive contrary to Ch III of Constitution – Whether separation of plaintiff from Australian community pending removal constitutes legitimate and non-punitive purpose – Whether detention of plaintiff reasonably capable of being seen as necessary for legitimate and non-punitive purpose.

Immigration – Unlawful non-citizens – Detention pending removal from Australia – Where no real prospect of removal of plaintiff from Australia becoming practicable in reasonably foreseeable future – Whether detention of plaintiff authorised by ss 189(1) and 196(1) of Act – Whether application for leave to reopen statutory construction holding in Al-Kateb should be granted.

Words and phrases – "alien", "conservative cautionary principle", "deportation", "deprivation of liberty", "executive detention", "habeas corpus", "indefinite detention", "judicial function", "judicial power of the Commonwealth", "legitimate and non-punitive purpose", "Lim principle", "penal", "power to exclude", "practicable", "punishment", "punitive", "real prospect", "reasonably capable of being seen as necessary", "reasonably foreseeable future", "removal from Australia", "separation from the Australian community", "unlawful non-citizen".

Constitution, s 51(xix), Ch III. Migration Act 1958 (Cth), ss 3A, 189, 196, 198.


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88 vailing more by prudence than strength, deriders for the time being, scholars, trustworthy, contentious, quarrellers in a fray, concupiscent, inflamed with unnatural lust, reflective, estranged from their own homes, giving dissatisfaction in everything, accusers, like madmen in their cups, scorners, year by year losing something, serviceable in friendship through goodness; they, in the majority of cases, end their days in a foreign land.

Those, however, who are born in Taurus will be of the following description: round head, thick hair, broad forehead, square eyes, and large black eyebrows; in a white man, thin veins, sanguine, long eyelids, coarse huge ears, round mouths, thick nose, round nostrils, thick lips, strong in the upper parts, formed straight from the legs. The same are by nature pleasing, reflective, of a goodly disposition, devout, just, uncouth, complaisant, labourers from twelve years, quarrelsome, dull. The stomach of these is small, they are quickly filled, forming many designs, prudent, niggardly towards themselves, liberal towards others, beneficent, of a slow body: they are partly sorrowful, heedless as regards friendship, useful on account of mind, unfortunate.

Those who are born in Gemini will be of the following description: red countenance, size not very large, evenly proportioned limbs, black eyes as if anointed with oil, cheeks turned down, and large mouth, contracted eyebrows; they


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 GAGELER CJ, GORDON, EDELMAN, STEWARD, GLEESON, JAGOT AND BEECH-JONES JJ. The plaintiff is a stateless Rohingya Muslim. He was born in Myanmar between 1995 and 1997. He arrived in Australia by boat in 2012 and was taken into immigration detention on arrival under s 189 of the Migration Act 1958 (Cth) ("the Migration Act"). He was granted a bridging visa in 2014.

In 2016, the plaintiff pleaded guilty in the District Court of New South Wales to a sexual offence against a child. He was sentenced to imprisonment for five years with a non-parole period of three years and four months. Upon his release from criminal custody on parole in 2018, he was taken again into immigration detention under s 189(1) of the Migration Act.

Whilst still in criminal custody, the plaintiff had applied for a protection visa. His application was considered by a delegate of the Minister for Immigration, Citizenship and Multicultural Affairs ("the Minister") in 2020. The delegate found him to have a well-founded fear of persecution in Myanmar. On that basis, the delegate found him to be a refugee in respect of whom Australia had protection obligations. Having regard to his conviction, however, the delegate found there to have been reasonable grounds for considering him a danger to the Australian community. On the basis of that finding, the delegate found that the plaintiff failed to satisfy the criterion for a protection visa set out in s 36(1C)(b) of the Migration Act and for that reason refused to grant him a protection visa.

The Administrative Appeals Tribunal affirmed the decision of the delegate following which the Federal Court of Australia dismissed an application for judicial review of the decision of the Tribunal in 2022. That final determination of his visa application engaged the duty imposed on officers of the Department of Immigration, Citizenship and Multicultural Affairs ("the Department") by s 198(6) of the Migration Act to remove the plaintiff from Australia as soon as reasonably practicable. Also in 2022, the plaintiff wrote to the Minister requesting his removal. That request engaged another duty imposed on officers of the Department by s 198(1) of the Migration Act to remove the plaintiff from Australia as soon as reasonably practicable.

By reason of the finding that the plaintiff had a well-founded fear of persecution, and in the absence of any relevant change of circumstances, the operation of s 197C(3) of the Migration Act was such that s 198(1) and (6) did not require or authorise an officer to remove him to Myanmar. In any event, he does not have any right of entry to or residence in Myanmar. The plaintiff had relatives in Saudi Arabia and in Bangladesh. But there was no real prospect of him being


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Rh conquer all things, they retain whatever possessions they acquire, they are extremely rich, penurious, niggardly of what is peculiarly their own, profuse in the pleasures of women, equitable, musical, liars. And the same by nature are learned, reflective, inquisitive, arriving at their own decisions, concupiscent, sparing of what belongs to themselves, liberal, quiet, prudent, crafty, they form many designs, calculators, accusers, importunate, not prosperous, they are beloved by the fair sex, merchants; as regards friendship, not to any considerable extent useful.

Those born in Cancer are of the following description: size not large, hair like a dog, of a reddish colour, small mouth, round head, pointed forehead, grey eyes, sufficiently beautiful, limbs somewhat varying. The same by nature are wicked, crafty, proficients in plans, insatiable, stingy, ungracious, illiberal, useless, forgetful; they neither restore what is another's, nor do they ask back what is their own; equitable, musical, liars. And the same by nature are learned, reflective, inquisitive, arriving at their own decisions, concupiscent, sparing of what belongs to themselves, liberal, quiet, prudent, crafty, they form many designs, calculators, accusers, importunate, not prosperous, they are beloved by the fair sex, merchants; as regards friendship, not to any considerable extent useful.

Those born in Leo are of the following description: round head, reddish hair, huge wrinkled forehead, coarse ears, large


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90 development of neck, partly bald, red complexion, grey eyes, large jaws, coarse mouth, gross in the upper parts, huge breast, the under limbs tapering. The same are by nature persons who allow nothing to interfere with their own decision, pleasing themselves, irascible, passionate, scorners, obstinate, forming no design, not loquacious, indolent, making an improper use of leisure, familiar, wholly abandoned to pleasures of women, adulterers, immodest, in faith untrue, importunate, daring, penurious, spoliators, remarkable; as regards fellowship, useful; as regards friendship, useless.

Those born in Virgo are of the following description: fair appearance, eyes not large, fascinating, dark, compact eyebrows, cheerful, swimmers; they are, however, slight in frame, beautiful in aspect, with hair prettily adjusted, large forehead, prominent nose. The same by nature are docile, moderate, intelligent, sportive, rational, slow to speak, forming many plans; in regard of a favour, importunate; gladly observing everything; and well-disposed pupils, they master whatever they learn; moderate, scorners, victims of unnatural lusts, companionable, of a noble soul, despisers, careless in practical matters, attending to instruction, more honourable in what concerns others than what relates to themselves; as regards friendship, useful.

Those born in Libra will be of the following description: hair, thin, drooping, reddish and longish, forehead pointed


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 Anna tossed her head as if to get rid of a disagreeable thought.

"When shall we go? The sooner the better. Tomorrow we can't, but the day after,"

"Yes .... no .... wait! Day after to-morrow is Monday. I shall have to go to maman" said Vronsky, somewhat confused; because, as he mentioned his mother's name, he saw Anna's eyes fixed with a look of suspicion on him, and his confusion increased her distrust. She forgot the queen of Sweden's swimming-teacher in her alarm about the Princess Sorokin, who was living at a country seat in the suburbs of Moscow with the old countess.

"Can't you go there to-morrow?"

"Why, no! That 's impossible. There is some business that I must attend to,—a power of attorney; and the money will not be ready to-morrow."

"If that is so, we won't go at all."

"But why not?"

"I won't go if it is put off later. Sunday or never!"

"Why so?" cried Vronsky, in astonishment. "There's no sense in that."

"It has no sense for you, because you never take me into account at all. You can't understand my life. The only thing that interests me here is Hannah. You say that it is hypocrisy. You said last evening that I did not love my daughter, but that I pretended to love this English girl, that this was affectation. I should like to know what can be natural in the life I lead here?"

For an instant she came to herself, and was frightened because she had broken her vow. But, though she knew that she was dashing to destruction, she could not resist the temptation of proving to him that he was in the wrong, she could not help heaping insults on him.

"I never said that: I said that I did not sympathize with this sudden tenderness for her."

"Why do you, who boast of being straightforward, tell me a lie?"

"I never boast, and I never tell lies," said he, re-

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 of the narrative, though it is not a very satisfactory explanation of the symbols. It converts the terms expressive of spiritual thought into natural ideas; and this, so far as we have observed, is not the scriptural method of conveying revelation to the world. On the contrary, the Apostle informs us that "the invisible things of Him from the creation of the world are clearly seen, being understood by the things that are made." Surely the natural "heaven" is employed in Scripture to signify a spiritual idea; and there can be no doubt that the natural "winds" are made use of for a similar purpose. In the original tongue both spirits and winds are expressed by the same word; thus, "The wind bloweth where it listeth, and thou hearest the sound thereof, but canst not tell whence it cometh, or whither it goeth; so is every one that is born of the Spirit."

But surely it cannot require much argument to convince those who will think in freedom upon the subject, that the description of the Lord's coming in the clouds of heaven, with angels and the sound of a trumpet, and gathering mankind from the four winds, is purely figurative of some spiritual events in connection with the Lord's Church and the souls of men. And this being so, the common opinion upon the subject requires a careful revision, because it is founded upon a merely natural interpretation of terms which plainly have a spiritual significance.

In the Revelation, the Lord is spoken of as coming to judgment upon a white horse, with eyes like a flame of fire, having many crowns upon His head, being clothed with a vesture dipped in blood, and the armies of heaven following Him upon white horses. But it is easy to see that this was never intended to be understood as a literal description of the Lord's advent to effect His judgment.


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 pressing the anger which was rising within him; "and I am very sorry if you do not respect...."

"Respect! That was invented to cover up the lack of love. If you don't love me any more, it would be better and more honorable to say so."

"No! this is becoming intolerable," cried the count, suddenly leaping from his chair; and, standing in front of her, speaking in measured tones: "Anna," he asked, "why do you try my patience so?" and she could see how he was holding back the bitter words that were ready to escape him. "It has its limits."

"What do you mean by that?" she cried, looking with terror at the unconcealed expression of hate on his whole face, and especially in his fierce, cruel eyes.

"I mean...." he began. Then he stopped. "I have a right to demand what you wish of me."

"What can I wish? I can only wish that you do not abandon me, as you are thinking of doing," she said, comprehending all that he left unsaid. "Everything else is secondary. I wish to be loved; but love is gone. All is over."

She turned toward the door.

"Stop! sto-op!" said Vronsky, still darkly frowning, but holding her by the arm. "What is the trouble? I said that it is necessary to postpone our starting for three days, and you answer by saying that I lie and am dishonorable."

"Yes; and I repeat it that a man who throws it into my face that he has sacrificed everything for me," said she, alluding to a former quarrel, " is worse than dishonorable: he is heartless."

"That settles it; my patience is at an end," cried Vronsky, quickly dropping her hand.

"He hates me; that is certain," she thought, as she went from the room in silence with tottering steps. "He loves some other woman; that is more certain still," she said to herself, as she reached her room. "I wish to be loved, but love is gone. All is over." She repeated the words that she had said,—"I must put an end to it."

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 The special surroundings of the narrative, the style, and the general structure of the whole book, may, indeed, in some measure account for this. We see no more reason for accepting the idea of the Lord's coming upon a natural cloud than we do for His coming upon a natural horse. Upon what reasonable ground can it be supposed that the angels who, in the one case, are spoken of as attending the Lord's advent, with a great sound of a trumpet, are to be literally thought of; and that the description of the armies of heaven, who, in the other case, are to attend His coming upon white horses, is not to be so understood? The questions cannot be satisfactorily replied to, and no distinctions can be drawn which are not of a purely arbitrary character. The fact is, that they are both symbolical narratives, and neither of them refers to events of which the natural world is to be the scene.

Although it is true that the Lord said "I will come again," the reflecting will see that this does not necessarily imply a personal coming, and a second sojourn amongst mankind in the world. By the work which He accomplished at His first advent. He can now come into the world with His benefits and blessings, in a way more influential than before. It must be admitted that He did for mankind at His first coming all that it was possible or necessary for Him to do by means of a personal appearing. If He did not, how can it be supposed that His work was completed? and, if it were completed, where is the necessity for another personal advent? He has come once in person, and He came also for judgment. This He has expressly told us; and, therefore, we conclude He must have accomplished all the work which came within the purpose of such an advent, and that another of the same kind is not


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 to be expected. His promise to come again when troubles should set in upon the Church, when false Christs and false prophets would arise, and deceive, if it were possible, the very elect; when it would become doubtful whether faith could be found in the earth, refers, so far as men in the world are concerned, to His re-coming into their minds by opening the interior truths of His word for their perception and acceptance. Hence, in connection with those remarkable predictions, it is expressly written, that the Son of man shall be revealed.

Besides, the Lord, in order to come personally into the world, took upon Himself a natural humanity. The humanity in which He was then seen by the common sight of His contemporaries, was taken from a human mother. That humanity, considered in itself, was not Divine, nor do we see how, by any subtleization or process of absorption, it could be taken up into the infinitude of the Divine nature. The Lord, during the whole period of His sojourn in the world, was engaged in putting off His natural humanity, and putting on another within it from Himself: and this is that Divine Humanity in which He now is, and in which He must ever be approachcd by those who love Him. It was this Divine Humanity which was revealed to the spiritual sight of the three disciples upon the Mount of Transfiguration, which was seen by His followers after His resurrection, and at the period of His ascension. This Divine Humanity is not adapted to the ordinary sight of men in the world, and none were permitted to behold it but those who had followed Him, and in some measure believed what He had taught. From the time of His resurrection, He was never seen by the natural eyes of any one; the reason being because He then no longer possessed


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 a natural but a Divine Humanity. The work was finished for the doing of which the natural humanity was provided; and provision was then made for a new or more spiritual intercourse with men, through the assumption of a Humanity that is Divine; and, therefore, He cannot reappear in the world of men without a re-incarnation, or in some other way reassuming a natural humanity, about which nothing is written in the Word; consequeutly, any future manifestations which He may make will not be to the natural eyes, but to the spiritual experience of mankind. Hence it appears to us that the promise of His coming ought to be understood as a coming to the spirits, and not to the bodies, of mankind; a coming to the perceptions of their minds, rather than to the sight of their eyes; and thus as a coming into the mental world by some enlightened teachings of His Word, and not as a corporeal appearing upon the clouds of the sky.

But what were the views entertained by the Apostles upon this subject? To answer this question correctly, we must not forget that the truths of Christianity which they finally adopted were gradually communicated to them. It was here a little, and there a little, and as they were capable of accepting them. The justice of this remark is clearly evident. The Lord laid down the principle of it when He said unto them, "I have many things to say unto you, but ye cannot bear them now;" and it is important to notice with what frequency they were at fault in rightly comprehending the teachings of their Divine Master. We are aware that this is delicate ground on which to step; but the opinions of men, not the facts of the case, have made it so. No one can carefully read what is written in the Word on this subject, without being satisfied with the truth of this


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PRINCIPLES OF ACCOMMODATION. 23 reason to believe that they fully explain all the changes of optical adjustment. It only remains to show more exactly how the changes in the lens are caused.

We start from the assumption that with perfect relaxation of accommodation the eye is adjusted for its far point, and that with each effort of accommodation it is adjusted for some less distant point. The simple suspension of accommodation causes a return to the optical adjustment for the far point. The truth of this sup- position is established by the fact that the eye may be adjusted for its far point artificially, by the use of atropine, or pathologically, by the paralysis of accommodation.

The phenomenon of accommodation is reduced accordingly to an antagonism between the elastic strength of the lens on the one. side and the zonula on the other, which is excited by the action of the ciliary muscle. The lens from its elasticity has a tendency to approach a spherical shape ; Helmholtz,* who first announced this fact, also found that with absolute relaxation of accommoda- tion for distant vision, the thickness of the lens is less than it is after death.

The zonula, which is stretched between the ciliary processes and the equator of the lens and is attached to both, tends by reason of its elasticity to flatten the lens. So soon as the zonula is re- laxed the lens will follow its own elastic tendency and will assume a greater convexity.

It may with the greatest probability be assumed that both the radiating and the circular fibres of the ciliary muscle act simul- taneously to relax the zonula. The elasticity of the lens then comes in play, and the above-described changes in its form occur; upon the cessation of muscular contraction the elastic tension of the zonula acquires the ascendency, and then occurs that flattening of the lens which corresponds to the condition of relaxed accom- modation.

It is advantageous in practice to possess a uniform standard of measure for the power of accommodation, in order to compare the

 * Physiol. Optik, pag. 110.


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24 RANGE OF ACCOMMODATION. results of examinations in diiferent individuals, or in the same individual under diiferent circumstances. Donders provided this standard in a very simple way by comparing the result of accom- modation to the optical value of a convex lens, which, if placed before the relaxed eye, would have accomplished the same as the accommodation does.

Let the lens X, in Fig. 7, be such that parallel rays striking its surface are focused at /. A screen at / would show distinct pic- tures of distant objects, just as a landscape camera obscura does.

Fig. 7.

If now the instrument be adjusted for some nearer point upon the axis, say at p, then, according to the rule, the distance between L and / would be increased ; if, however, this distance cannot be changed, there is still a means by which a distinct image of jj can be cast at f • for this purpose it is only necessary to combine with the lens L an auxiliary meniscus, L', which has such a focal length that rays proceeding from p, after their refraction in L', become parallel ; they then fall parallel upon X, and, according to the original supposition, are focused at /; now if, for instance, the distance from the point p to L' is 4 inches, then the convex me- niscus must evidently have a focal length of 4 inches ; its optical value would be expressed by +. The same principles can be applied to the eye. If before an emmetropic eye with relaxed accommodation we place a convex meniscus of +, the eye is thus adjusted for a distance equal to the focal length of tliis lens, that is, 4 inches. If the near point of an emmetropic eye is 4 inches distant, then the accommodation does for this eye just what was done by the convex meniscus for the relaxed eye. If we represent the accommodation by the letter A, we have as the measure of the accommodation of an eye whose far point is at an infinite distance, and whose near point is at 4 inches, the expres- sion x=5. The optical value of the accommodation is thus best expressed by the principal focal distance of that convex lens which, added to the condition of refraction in the eye, would com-


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RANGE OF ACCOMMODATION. 25 plete an apparatus adjusted for the nearest point upon which the eye could have been adjusted by its own physiological power.

The near point p corresponds always to the optical adjustment of the eye when to its anatomical condition of refraction (deter- mined by the position of the far point r) the result of accommo- dation is added. Expressed in an optical formula we have tH" i = j;, — that is, refraction plus accommodation gives the near point. An immediate deduction from this is the expression ^=j — t, — that is, when we know the positions of the far and near points we can calculate the range of accommodation. The value which we obtain assumes the form of a fraction wdiose numerator is 1 and whose denominator expresses in inches the principal focal length of that convex lens which placed in front of the relaxed eye would have accomplished the same as the accommodation.

The same method of mathematical expression is employed for the relative range of accommodation, which is generally denoted by A'.

We found, for example (page 18), with a convergence upon a point 12 inches distant, that the relative far point lay at 48 inches, and the relative near point at 6 inches ; from this we can calculate the value of the relative range of accommodation, x' = 1 — -lg=-^. The negative part of the relative range of accom- modation is in this case -^q, the positive yj-

Having thus obtained a common measure for the range of accommodation in different individuals, Donders further showed that the extent of the range of accommodation depends upon the age of the individual. With the increase of years the near point moves gradually from the eye, and the range of accommodation is thereby reduced. Two possibilities suggested themselves by which to explain this phenomenon: either the power of the muscle of accommodation must weaken, or there must be changes in the elasticity of the lens. The circumstance that the range of accommodation is already noticeably diminished at a time when the strength of all other parts of the muscular system is unimpaired must banish the idea of a premature loss of power in the muscle of accommodation; on the other hand, however, there are all-sufficient proofs of changes in the lens dependent upon age.


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26 PRESBYOPIA. It is known that tlie lens becomes harder with age. From the investigations of F. J. v. Becker,* this hardening begins at a very- early age, affecting first the nucleus of the lens and spreading to the periphery. At -a later age this hardening may be plainly recognized by the stronger reflection of light observable upon focal illumination of the lens. It is fair to assume that with the change in the index of refraction there occurs also a change in the elasticity of the lens, so that it gradually loses the power to respond to the contraction of the ciliary muscle by increasing the convexity of its curved surfaces.

The gradual withdrawal of the near point causes at first no in- convenience. According to Donders, the average distance of the near point in the emmetropic eye at 20 years of age is 3f inches, at 35 years about 6 inches : and it is very seldom that there is occasion to use the eyes upon objects so near. When the near point recedes to 15 inches or more, inconvenience is felt in all oc- cupations which require distinct vision of near objects, such as reading, sewing, etc. If the objects are placed within the region of distinct vision, — that is, beyond the near point, — the retinal images become too small to admit of continuous vision ; upon bringing the objects within the near point the retinal images be- come larger, but at the same time are rendered indistinct by cir- cles of diffusion. This indistinctness of the retinal images is less than it otherwise would be from the fact that simultaneously with the limitation of accommodation the pupil becomes smaller and the circles of diffusion are correspondingly decreased. PresbyojDes seek, therefore, in every occupation the greatest possible amount of light; in the evening, for instance, when reading, they will hold the light between the book and their eyes in order by strong illumination to reduce as much as possible the size of the pupil.

The senile changes in the lens cause not only a withdrawal of the near point, but may affect the far point in the same way. The lens is known to consist of a great number of layers, whose in- dices of refraction increase from the periphery toward the centre, and it has been proved that by reason of this arrangement the resulting focal length is shorter than it would be if the entire lens possessed the refracting power of the nucleus. Now, we

 * Arch. f. Ophth., Bd. ix. 2, pag. 19.


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Rh have ground to believe that from the senile changes of the lens its cortical part becomes harder, so that its refracting power more nearly approaches that of the nucleus; an increase of focal distance is the result. Moreover, in extreme old age the lens appears to become actually flatter, a further cause for the diminution of refraction. In this way hypermetropia may develop in eyes originally emmetropic.

The diminution of the range of accommodation by a withdrawal of the near point from the eye is, then, to be called presbyopia only when it is a co-symptom of senile changes in the eye. These changes are numerous. All the refracting media of the eye become less transparent; this is noticeable when one compares ophthalmoscopically a senile eye with a youthful one; the anterior chamber becomes shallower; the iris loses its motility; the pupil becomes smaller, and often does not dilate normally upon the use of atropine; the choroid and membrane of Descemet (the last, fortunately, as a rule, only near the corneal margin) become thickened and uneven; phosphate of lime, as Donders has shown, is deposited in the sclera; the muscle of accommodation atrophies; the retina in its vessels and in the structure of its peripheral parts also shows changes which must be regarded as senile. Diminished clearness of vision follows all these phenomena. We thus find presbyopia to be a co-symptom of a considerable series of changes, and must, therefore, regard the withdrawal of the near point as a normal phenomenon only when it stands in due proportion to the age. Emmetropes, on an average, first experience the inconveniences of presbyopia between the forty-fifth and fiftieth years of life. Only very sharp-sighted eyes can, at a greater age, be used by the hour in reading or writing without experiencing fatigue.

Premature presbyopia occurs in connection with premature marasmus, after prostrating sicknesses, with incipient cataract and with the development of glaucoma.

The diagnosis of presbyopia is easy. It is first to be ascertained that the vision for distance is good, then that the indistinctness of near objects is corrected immediately by weak convex lenses, and, finally, that the diminution of accommodation stands


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28 PRESBYOPIA. in the proper relation to the age of the patient. Paralysis of accommodation is partly thus excluded, partly, also, by the beha- vior of the pupil. As a rule, the pupil is contracted in presbyopia and dilated in paralysis of accommodation.

The treatment consists in substituting convex lenses for the lost power of accommodation. So soon as presbyopia causes incon- venience which is relieved by the use of weak convex lenses {-^ to 4^), such spectacles should always be used for work. It is useless, by straining the eyes, to attempt to postpone the use of glasses, and it is equally useless to a'dopt them so long as, in spite of the removal of the far point, continuous reading or writing causes no inconvenience.

The strength of the glasses to be prescribed depends upon the nature of the patient's occupation. The farther his near point has receded beyond the distance of the objects on which he uses his eyes, the stronger the glasses which he requires. For reading and writing it generally suffices to bring the near point up to a distance of from 12 to 15 inches. In simple, uncomplicated presbyopia, with fair acuteness of vision, the choice of proper spectacles may usually be left with the patient. From time to time, as the near point gradually recedes from the eye, somewhat stronger glasses must be chosen. For healthy eyes it is better to use uncolored glasses. The blue ones, which have become per- haps too fashionable, are at first very agreeable, but since they deprive the retina of the normal stimulus of white light, the eye becomes too sensitive; hence having once begun, it is necessary to continue wearing them.

We have said that in making the diagnosis of presbyopia it is necessary to determine the acuteness of vision ; we must now con- sider the method of doing it. A sufficient judgment may be formed by trying the acuteness of vision by test type of varying sizes, such as Jaeger's. In many respects, however, Snellen's test letters are better. They are more exact, and the results are more easily compared with each other. These letters increase in size according to a definite proportion.

The most suitable objects appear to be black letters, of sizes so arranged that they are seen plainly by the normal eye under


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DETERMINING ACUTENESS OF VISION. 29 an angle of five minutes. The thickness of the lines and smaller parts of the letters is exactly one-fifth their height, so that the dif- ferent parts of the letters are included in an angle of one minute, while the whole letter is included in an angle of five minutes. The letter C, for example, in comparison with the letter O, shows an interruption with a visual angle of one minute. Accordingly this series of letters is so arranged that the test letters, No. I, one foot distant, No. II, two feet distant, No. XX, twenty feet distant, and No. C, one hundred feet distant, are all included in the same visual angle of five minutes. If, for iustanee. No. XX is dis- tinctly seen at twenty feet, but not No. I at one foot, it shows normal acuteness of vision, but that probably the accommoda- tion is insufficient to adjust the eye for a distance of one foot. This probability becomes a certainty if by the use of the proper convex lenses No. I is also plainly seen at a distance of one foot.

Again, if No, I is seen distinctly at a distance of one foot, but not No. XX at twenty feet, there is normal acuteness of vision, but there is reason to suspect the existence of myopia. This suspicion is confirmed if with the proper concave lenses No. XX is seen distinctly at twenty feet.

If after the correction of any existing anomaly of refraction the patient cannot see No. XX at a distance of twenty feet, but only at a distance of perhaps ten feet, there exists a deficiency in the acuteness of vision. The degree of this deficiency may be expressed by a fraction whose numerator is the number of feet at which the letters are seen, and whose denominator is the number of feet at which they should be seen. In the example just given there is an acuteness of vision of 1|- = i.

The examination of the condition of vision is conducted as follows. The test letters are set up in a well-lighted position in a room twenty feet long or more. If now, for example, No. XX is read at a distance of twenty feet, the acuteness of vision is |-|, that is = 1. Persons who see No. XX at more than twenty, say at twenty-five feet, possess an acuteness of vision of ff, or one exceeding the normal average ; such cases are not uncommon among young individuals. If, on the contrary, No. XX is not seen at a distance of twenty feet, but the patient must ajiproach nearer in order to distinguish the different letters, there is a dimi-


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30 nution in the acuteness of vision, and it is to be expressed in the manner above described.

It is in many respects more convenient to allow the distance between the test letters and the patient's eye to remain unchanged, and to write as numerator of the fraction the number which is seen with normal vision at that distance, and as denominator the number which the patient actually sees; for instance, if not No. XX but No. LXX are the smallest letters to be seen at a distance of twenty feet, the acuteness of vision is j^.

In using these test letters it should be remembered that it is by average daylight that the letters are recognized at the given distances. AVith intense illumination they can be seen at even a greater distance. The changes in the intensity of daylight, which are dependent upon variations in the weather, are a source of error difficult to avoid.

The proposition to abandon daylight and conduct this examination by artificial light is also objectionable, for artificial light is likewise subject to considerable variations of intensity, is difficult to control, and further, when we conduct a patient out of the daylight into a room artificially lighted in order there to try his acuteness of vision, an adaptation of the retina to the changed illumination must first take place. The laws according to which the retina adapts itself, especially in pathological conditions, to light of different degrees of intensity, are as yet imperfectly understood.

The unavoidable variations in the intensity of daylight seem the simplest to deal with. In my own private practice I have found it convenient to use a modification of the usual expression for the acuteness of vision. If, according to Snellen's plan, the denominator of the fraction be the number of the test type recognized by the patient, and the numerator the number of feet at which he sees them, then it is only the denominator which is affected by changes in the illumination; the errors from this source become less when we subject the numerator also to the same influences. I prefer, therefore, to write as numerator of the fraction that number of the test type which I can recognize simultaneously with and at the same distance as the patient; as denominator, I write the number of the type which the patient reads. In this way some but not all sources of error are avoided.


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MYOPIA. '31

Myopia exists when, accommodation being relaxed, parallel rays falling upon the cornea are not united to an image-point upon the retina, but intersect each other in front of it. Of course under these circumstances every distant object casts upon the retina a circle of diiFusion. The retinal images of distant objects are there- fore diifuse and indistinct. In order to cast a sharp image upon the retina the luminous point or object fixed must approach the eye to within a certain distance. The far point of distinct vision does not lie as M'ith the emmetropic eye at an infinite but at a finite distance.

The position of the far point can be directly determined by ascertaining the greatest distance at which test type of the proper size can be read. If, for instance, the patient read No. I of Snellen's test type at 12 inches, but cannot read No. II at 24 inches, it may be assumed with certainty that his far point lies between 12 and 24 inches, and it remains, by further experiments, to determine more exactly its position.

It is advisable in all cases to begin the examination in this manner and then to verify and perfect the result by giving to the rays from a distant object, by the help of a concave lens, a divergence such as if they had proceeded from the far point. If, for instance, the far point lie at 16 inches, and we place imme- diately in front of the patient's eye a concave lens with a negative focal length of 16 inches, then will the parallel rays after their refraction in the concave lens so diverge as if they had proceeded from the negative focal point of the lens ; but according to our supposition this negative focal point coincides with the for point ; both lie 16 inches from the eye, the distance between the concave lens and the eye not being considered. Under these circumstances there is distinct distant vision, and upon using the test type for dis- tance, normal acuteness of vision is found. A concave lens weaker than — yig would not produce this result, for its negative focal ])oint would lie at a greater distance from the eye than the far point ; but with a stronger lens, for instance with — -^^ or — ^^, dis- tant vision is still possible; the rays falling parallel upon the lens diverge after their refraction in it, as if they had proceeded from a point 14 or 12 inches distant, and a myopic eye whose far point lies 16 inches distant, can by a slight effort of accommodation


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32 MYOPIA. adjust itself for these distances. Since, however, we wish to de- termine the optical adjustment of the eye when its accommodation is fully relaxed, we have the important rule that only the weakest concave lens with which distant vision is possible gives the proper expression for the position of the far point. One ought not to trust the subjective impressions of the patient ; his simple state- ment that he sees better, is not sufficient unless in connection with it the reading of the test letters shows a perceptible im- provement in vision. Weaker and weaker glasses should be tried till one is found which diminishes the sharpness of vision ; the limit is then passed.

If acuteness of vision be diminished, as is usually the case in the high grades of myopia, then the weakest concave lens which gives the best attainable vision must be regarded as giving ap- proximately the correct expression for the degree of myopia.

If the position of the far point requires the employment of a moderately strong concave lens, say — -^ or more, there is a very simple method of determining whether it is too strong or not. Move the lens, and of course at the same time its negative focal point, gradually away from the eye ; if with the lens close to the eye its negative focal point coincided with the far point, then upon withdrawing the lens its focal point will be removed beyond the far point, and vision loses its distinctness; if upon Avithdrawing somewhat the lens vision is as distinct or even more distinct than with the lens held close to the eye, it shows that the concave lens is too strong. In the case of strong concave lenses the distance between the eye and the lens should not be neglected ; if, for instance, it be ^ inch and the far point lie at 3 inches, then will the negative focal point of a lens — ^^ coincide with the far point.

The degree of myopia is determined by the position of the far point; if it lie at 16 inches the degree of myopia is expressed by M^; if it lie at 3 inches, by M^. That concave lens whose negative focal point corresponds with the far point is called the neutralizing lens. The far point of an eye provided with a neu- tralizing lens lies, as it does in the emmetropic eye, at an infinite distance.

Formerly the optical cause of myopia was thought to be too great a curvature of the cornea. By ophthalmometric measure-


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Rh ments, Donders attained the unexpected result that the radius of curvature of the cornea is generally greater in the case of myopes than with emmetropes. Of course a too great curvature of the cornea, when it exists, will cause myopia. The same is true of the lens. Changes in it may cause myopia, but such cases do not often occur. A forward displacement of the lens must, for optical reasons, increase the refractive condition; this seems, however, to be an infrequent cause of myopia. Shortsightedness seems to be oftener caused by an increase of the index of refraction, particularly in the nucleus of the lens. The condition may be easily recognized ophthalmoscopically, if the pupil be large enough, or has been dilated by mydriatica. The reflection from the nucleus of the lens is generally stronger than normal, as well upon examination by daylight with the naked eye as by focal illumination; upon ophthalmoscopic illumination, especially with a weak mirror, the nucleus appears evidently differentiated from the cortical part of the lens; this can be best seen by making slight movements of the mirror. These changes occur as the prodroma of nuclear cataract, both in eyes previously healthy and in those recovered from glaucoma. They often occur, also, as one of the many complications of myopia depending upon an elongation of the axis of the eye. Under the title "Diseases of the Accommodation" it will be shown that apparent myopia may be caused by a continuous tension of the accommodation.

The most frequent and important cause of myopia is the elongation of the axis of the eye. The other diameters are not unfrequently somewhat increased. As a rule, however, the axis is most elongated, and the eye assumes therefore an ellipsoid form. The distention of the membranes occurs mostly at the posterior part of the eye, involving generally the region of the optic nerve. The greatest diameter of the eye, therefore, very nearly coincides with its axis; it may, however, deviate laterally, generally toward the median side. According to E. v. Jaeger, the greatest expansion may occur even on the median side of the optic nerve.

This anomaly of form was first described by Scarpa. Its designation as "staphyloma posticum" is not exactly appropriate, inas-


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34 much as in uncomplicated myopia the protrusion is by no means so circumscribed and prominent as in anterior scleral staphyloma. In spite of the elongation of the axis, the eye maintains, as shown in Fig. 8, a regular form. The sclera is expanded and thinned throughout its whole extent, on the temporal more than on the median side, and most of all in the region of the posterior pole. So thin may it become that this part upon enucleated eyes appears blue, like an anterior staphyloma, and if the cornea be turned to the light, an inverted image of outer objects will be plainly seen cast upon the attenuated portion. Indeed, even during life the bluish color in the region of the posterior pole can be often seen by causing the patient to turn his cornea strongly inward.

Fig. 8.

After Domlers, Anomalien der Refraction, etc, Fig. 145.

These changes exert a marked influence upon the place where the optic nerve enters the eye.

The stretching of the membrane in the region of the posterior pole pushes the optic nerve somewhat aside toward the median line.

Fig. 9.

From Bonders, l. c. Fig. 147. The space c between the inner and outer nerve-sheaths widens as it approaches the sclera; the largest part of the outer sheath a" blends with the sclera; a thinner membrane, a', runs toward the optic nerve, and is continuous with the inner nerve-sheath b'. At this place the sclera consists therefore of only a thin lamella, a', which is in relation posteriorly with the loose areolar tissue c', and which anteriorly is covered by the atrophied and depigmented choroid d'; f is the lamina cribrosa, and the tissue n, above the choroid, is the retina.

Moreover, the two nerve-sheaths change in their relations toward each other. Since the inner nerve-sheath is adherent to the nerve itself, while the outer one is continuous with the sclera, it follows that a distention of the latter causes a traction upon the external sheath, drawing it from the other and increasing the space between the two. (See Fig. 9.)


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MYOPIA, ANATOMICAL CHANGES. 85 According to Dondcrs, the place of entrance of tlie optic nerve on the outer surface of the sclera may attain by this widening a diameter of 8 millimetres or more, so as to present an appearance as if the optic nerve Avere set upon a second terrace of the staphy- loma. This widening of the space between the outer and inner sheath of the optic nerve is mentioned by Von Ammon.*

The investigations of E. v. Jaeger f show that the same thing occurs in myopia of a low grade.

As a rule the choroid remains normal in its anterior part, but the more it approaches the expanded part the thinner, paler and more atrophied does it become. These changes are greatest close to the optic disc, so that here nothing remains of the choroid but a thin, structureless, transparent membrane, containing no trace of blood-vessels or even capillaries. Beyond this fully-atrophied part, however, the anatomical elements of the choroid are but little changed. The pigmented epithelium forms a uniform layer ; the individual cells lose more or less of their pigment molecules in the greatly distended part, and may even become colorless ; in places they are noticeably enlarged and flattened. The branching pigmented cells of the choroidal stroma behave in the same way ; anteriorly, where the choroid retains its normal thickness, they remain entirely normal ; further back they con- tain less pigment, and finally none at all.

A further consequence of the distention suffered by the choroid is that its anterior portions, the ciliary body, the iris and at the same time the lens, move backward ; this accounts for the very frequent deepening of the anterior chamber in myopic eyes. The ciliary muscle having a tendinous attachment on the edge of the cornea, experiences from this process a traction which may induce atrophy.

In uncomplicated cases of myopia the retina shows no recog- nizable changes.

In myopia, changes are almost always observable about the optic disc; as a rule there is a sharply-defined sickle-shaped or crescentic spot on the temporal side and close to the disc, where

f Einstellungen des dioptr. Apparates, Taf. ii. Fig. 18 bin 29.
 * Von Ammon, Zeitsclirift fiir die Ophthalinologie, Bd. ii. pag. 250.


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36 more or less atrophy of the choroid exists. In many cases it is only the pigmented epithelium, which is faded or degenerated so that the choroidal stroma can be distinctly seen. In most cases, however, there is an unmistakable atrophy of the stroma, and the entire choroid is transformed into a thin, structureless, transparent membrane, which does not weaken in any degree the white reflex from the sclera. In many cases one still sees a few large vessels remaining in the region of the choroidal atrophy. These various appearances are observed quite constantly. Often with a high degree of myopia, and with an atrophied part equal in width to the diameter of the disc, only the pigment-epithelium will have lost its color, while in other cases of a mild form of myopia there will be only a small but fully atrophied crescent about the margin of the disc.

The atrophied part is often separated from the adjoining choroid by a rather regular dark line. Some cases, where the atrophy has extended farther over the choroid, show traces of several such concentric curved lines. In other cases the atrophied part has a more or less irregular form.

In the majority of cases this circumscribed choroidal atrophy occurs on the temporal side of the optic nerve, and spreads from it toward the macula lutea, generally, however, without reaching it. The increase of the atrophied region does not depend alone upon an implication of the adjoining choroidal tissue in the degenerative process, but at the same time upon a further stretching of the already thin and yielding part; in this way the distance between the macula lutea and the optic nerve increases, and the latter becomes more displaced toward the median line.

In high degrees of myopia the choroidal atrophy often extends around the entire optic nerve; the disc appears surrounded by a white ring, whose breadth is generally greater on the temporal than on the median side.

In rare cases the atrophied spot is below the optic nerve; oftener its position is under and outward, or over and outward, from the optic nerve. Its rarest position is above the optic nerve, and such cases do occur. A beginning of the choroidal atrophy upon the median side of the optic nerve has been observed.


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MYOPIA, OPHTHALMOSCOPIC APPEARANCE. 37 These small atrophied spots often seem to lie at a different level from the other parts of the fjindus, — at least it is often no- ticed that the retinal vessels in passing from the periphery upon the atrophied part experience a change of direction, which is to be regarded as the expression of a transition from one surface to another lying deeper. Donders* and Manthnerf regard these cases as exceptional, and I have also formerly expressed my- self in the same way, since in cases of a high degree of myopia, with wide-spread choroidal atrophy, I missed the oplithalmo- scopic signs of the difference of level. The case is somewhat dif- ferent with the crescentic spots of moderate size with a breadth less than that of the disc. Especially when they are sharply bounded and surrounded by the dark line before described, do they give the impression of a slight ectasia. The optic disc shows generally in these cases where the ectasia affects it only on one side, an oblique position, the side corresponding to the greatest diameter of the ectasia lying deepest ; and besides this, we have such a change of form of the optic nerve that its transverse sec- tion forms an oval, whose shortest diameter lies in the same direc- tion as that in M'hich the ectasia has attained its greatest extent. This change of form of the optic nerve is, in part certainly, only an apparent one; its dislocation toward the median wall of the eyeball causes us to see it in a more oblique position than normal, and therefore foreshortened ; still more must this be the case where the disc has suffered the oblique excavation above described. Where the choroidal atrophy is of slight extent, the contour of the optic nerve is generally sharply distinguishable from the ad- joining white scleral region. If the atrophy involves a large j^art of the fundus, the demarcation of the optic disc generally becomes very indistinct.

The retinal vessels show with unusual distinctness upon the white background of the sclera ; for this reason they are often visible in greater numbers ; they are, moreover, less sinuous than normal.

The choroid bordering upon the atrophied spot may appear wholly unchanged, but sometimes shoM'S traces of a slight degree of atrophy ; it appears somewhat lighter and more transparent,

 * L. c, pag. 300. t L. c, pag. 421.


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38 and its intervascular spaces in consequence of its stretching are somewhat widened.

This circumscribed choroidal atrophy is almost always present in myopia, and according to Donders there is a quite uniform average relation between the extent of the atrophy on the one hand and the degree of myopia and time of life on the other. It must be mentioned, however, that in this respect there are very considerable individual variations. The consecutive atrophy may be very slight, with a quite high degree of myopia; and, on the other hand, in emmetropes, and even in hypermetropes, these white, crescentic, slight ectasias are sometimes seen upon the temporal side of the disc; they are observed oftener in old than in young persons. The condition of refraction not considered, the ophthalmoscopic appearances in many of these cases are exactly the same as in myopia. On the other hand, however, it is unmistakable that in this matter there are very gradual transitions, so that in any given case one cannot be certain whether he has before him an atrophied crescent or a rather broad "scleral stripe."

At all events, the connection between myopia and atrophy of the choroid is undoubted. It only remains to be explained why it develops so constantly on the temporal border of the optic nerve, and not on that part of the choroid lying near the visual axis. It is to be remembered that around the optic nerve the choroid is closely attached to the sclera, that often too it sends fibrous processes into the nerve itself. At this place, therefore, the choroid cannot so easily escape the strain as it can in other localities where it is more loosely connected with the sclera. Now, since the eye is most distended in its antero-posterior diameter, it is easy to see why the choroidal atrophy should begin just upon the temporal side of the optic nerve.

Nevertheless, the sharp demarcation which many of these cases show, proves that certain local causes limit the effect of the distention of the entire choroid to a sharply circumscribed region. So, too, the fact that the atrophy often extends entirely around the optic nerve shows that the nerve itself participates in the process. In this connection the widening of the space between the two


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MYOPIA, OPHTHALMOSCOPIC APPEARANCE. 39 nerve-sheaths recurs at once to the mind. The elongation of the sagittal diameter stretches the sclera equally with the choroid, and a traction must necessarily be brought to bear upon the outer nerve- sheath, which is continuous with the sclera. The outer nerve- sheath yields to this traction, separates from the inner sheath, the lamellas of the sclera nearest the disc (Fig. 9, a'h') lose their sup- port and become stretched and thinned in proportion as the space between the sheaths becomes greater. The same happens with the choroid, which maintains its normal attachments to the inner surface of the sclera, the border of the optic nerve and the lamina cribrosa. It is easy to understand why this exceedingly thin place should yield to the normal intraocular pressure, and thus form an ectasia, which, to be sure, is generally slight. Exter- nally this is not perceptible, since it is too small and is covered by the external nerve-sheath. These conditions, however, are no obstacle to the ophthalmoscopic examination. For the recognition of this condition the choroid need not be fully atrophied; with a very slight atrophy of the choroid about the optic nerve the course of the retinal vessels is often sufficient to determine the existence of a slight ectasia.

If in a high degree of myopia the greatest diameter of the eye coincide nearly with the visual axis, the outer optic nerve-sheath appears to separate on all sides from the inner one, and the cho- roidal atrophy assumes the annular form. Donders states that such was the case in the eye whose optic nerve is represented in Fig. 9.

Of course in high degrees of myopia the diffuse atrophy of the choroid caused by the stretching of the ocular membranes may easily overstep the limits bounded by tlie outer nerve-sheath. Nevertheless, one often sees in these cases upon the white scleral background which has been laid bare by the choroidal atrophy, a distinct curved line, which may be regarded as probably the line of junction of the external nerve-sheath with the outer surface of the sclera,

In the majority of cases myopia, or at least a predisposition to it, is to be regarded as congenital or inherited. On the other hand it is certain, and one hears it often enough confirmed by the


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40 myopes themselves, that straining the eyes favors the development of myopia.

The clinical history of hypermetropia shows that a long-continued tension of accommodation is of itself not enough to induce an elongation of the eye. Nevertheless it might be otherwise if the sclera possessed diminished power of resistance, and if other conditions were present, particularly strong convergence of the visual axes and a bowed position of the head. The first is associated with an increased intraocular pressure, which favors a distention of the sclera; the last causes a passive hyperæmia, which tends in the same direction. All these conditions almost of necessity exist when work is undertaken in an insufficient light. The habit which children early acquire of reading long into the twilight, and the use of ill-contrived school-furniture, are both frequent causes of myopia.

Accordingly, it is no wonder that myopia is such a wide-spread abnormity. It occurs in early childhood, and shows with the increase of years a progression both in frequency and degree of development.

Although for the majority of cases we must regard a congenital weakness of the posterior part of the sclera as the primary cause of myopia, it is certain that the same condition may be an acquired one. The circumstance that myopia often develops in children shortly after measles or scarlet fever goes to prove this. Myopia often occurs also in connection with cloudiness of the cornea; this is not because the cornea becomes more convex, for in most cases there are simultaneously present the ophthalmoscopic indications of elongation of the axis; it is more probably due to the indistinctness of the retinal images, the patient seeking to compensate by increase in size for what he loses in distinctness. In order to obtain larger retinal images, the patient brings his eye as near as possible to his work; a bowing of the head, strong tension of accommodation and a corresponding convergence of the visual axes are the consequences.

If the distention of the sclera be once established, it can be easily understood how intraocular hyperæmia and conditions of slight irritation may still further lessen its capacity for resistance and render the distention progressive. On the other hand, one often sees, in cases with great distention of the sclera and high


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MYOPIA, CAUSES AND COURSE. 41 degree of myopia, choroidal changes which must be regarded as inflammatory. This, however, does not justify us in regarding the process as an inflammatory one from the beginning, and tlie atrophied crescent as tlie result of a sclerotico-choroiditis poste- rior.

Myopia may remain stationary through life, or at an advanced age it may show an apparent or actual decrease. The apparent decrease is due to the contraction of the pupil, by which the circles of diffusion are made smaller and the images of distant objects more distinct. An actual decrease of myopia may be caused by the senile changes in the lens before referred to.

In other cases myopia is rapidly progressive during a certain period of life, generally up to about the twenty-fifth year, and after that remains stationary. Finally, it may happen that myopia remains progressive through life,

The myope receives with the naked eye only indistinct, diffuse retinal images of all objects lying beyond his far point. In low degrees of myopia the indistinctness of distant vision is often not so great as to cause marked inconvenience, but the opposite is true in high degrees of myopia, where the retinal images of ob- jects only a few feet distant are very confused. If, moreover, the objects are insufficiently illuminated, as in the twilight, vision will be very imperfect.

The size of the circles of diffusion increases with the distance of the object and the size of the pupil.

Myopes are often better able than emmetropes to recognize very small objects, even in a poor light, since the jx)sition of the near point allows a closer approach of the object.

As the far point approaches the eye, the whole range of accom- modation approaches with it, so that without any lessening of the angle included by the accommodation the space covered by accom- modation is greatly diminished. If, for instance, with MyL the action of accommodation is as great as we have above assumed it to be in the emmetropic eye, that is ^=1, the position of the near point may be calculated from the formula -f -j- i:=^, which becomes ^2 + 4 = 3^- The whole region of distinct vision lies between the points 3 inches and 4 inches distant, while the

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42 emmetrope, with exactly the same amount of accommodative power, receives distinct retinal images from 4 inches up to an infinite distance.

The range of accommodation of myopic eyes may be determined by finding the positions of the far and near points, and reckoning from them the accommodation; or the examination may be made to resemble that of the emmetropic eye by removing the far point to an infinite distance, by the use of a neutralizing lens, and then finding the near point.

The behavior of the relative range of accommodation is of special interest. The myope learns unconsciously to converge nearly to his near point without accommodating. If, for instance, the far point lie at 8 or 10 inches, the eyes (of course without glasses) converge to nearly this distance without there being any simultaneous tension of accommodation.

Now, since myopes are much seldomer than emmetropes in a position to use their near points, it follows, by reason of the change in the relative range of accommodation, that less demand is made upon the accommodative power of the myopic than of the emmetropic eye.

In other respects, however, greater demands are often made on the myopic than on the emmetropic eye; particularly is this the case in reference to the convergence of the visual axes. If, with the naked eyes, the myope wishes to see distinctly and binocularly an object within his range of accommodation, his visual axes must converge to at least the distance of his far point. In only moderate degrees of myopia a stronger convergence is required than in emmetropic eyes. Moreover, the convergence is made difficult by two circumstances.

In emmetropic eyes the line of vision does not intersect the cornea at its centre, but somewhat toward the median side, A perpendicular let fall upon the centre of the cornea will form with the line of vision and on the external side of it an angle which we designate as the angle $$\alpha'$$. If the lines of vision are parallel, then the perpendiculars let fall upon the centre of the cornea must be divergent, and if the lines of vision intersect at any given point, the point of intersection of the perpendiculars must be at a greater distance. In myopia the deviation of the line of vision from the centre of the cornea is less than in emmetropia, and consequently


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 of my serious friend. Thinking the old veteran would relish their proposal as little as myself, I thought it would be agreeable to him, if I could prevail on the spirited sons of Mars not to urge the matter farther; addressing them in a jocose manner.

"Gentlemen, it seems you do not consider that these airy disturbers of nocturnal rest are not fond of large companies; or do you suppose the apparition, which I suspect to be a female one, a second Semiramis."

However, it was in vain to attempt persuading them to drop the adventure, their imagination having been heated too much by the Austrian's tale, as that they would give up their design: Turning their backs against me, highly displeased with my harangue, they solicited my friend with the greatest impetuosity to comply with their request. He inquired whether Lieutenant N was still an inhabitant of the haunted inn, and being told that the valiant son of Mars had


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 removed to another lodging the next morning after the nocturnal rencounter, he refused flatly to yield to their entreaties, telling them, he was sure the apparition would give them the slip.

"Well, well," exclaimed the undaunted warriors, "we will run the risk and watch the ghost, though we should sit up ten nights for it; we are determined to unfold that mystery."

So saying they left the room in great hurry.

"What do you think of the matter?" said I, when the visitors had left us.

"Nothing," replied he, with much sang froid, shrugging up his shoulders.

"But the ghost," said I.

"Is an offspring of their childish fancy;" replied the Austrian.


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 A

A new Map of GREENLAND.

By Mr. Miionary in that Country for twenty five Years. Tranlated from the

Printed for in  Row;  in ; and  near St. James's Gate. MDCCXLV.

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 "The fall of Lieutenant N," asked I.

"Is very natural," replied the Austrian, I could"I could [sic] cite you more than hundred incidents corroborating the truth, that people have a very confused idea when their senses are tied up by fear and anxiety.—As soon as cool reflection gives way to the horrors of a disordered fancy, we are but too apt to create phantoms and spectres around us, we do not see what really exists, but what we fear to behold."

I could oppose nothing to this reasoning of his, founded so strongly on experience, and suspected the courage of our valiant Lieutenant very much, having no doubt but his fear had made him miss the staircase; I therefore took no farther notice of our bravado and his companions, not caring what would be the finale of their trifling adventure. My friend was likewise quite unconcerned about the matter, and, without mentioning it any farther, we went about our business.


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 To His Mot Serene

Hereditary  Succeor to the  of

S I took the Freedom mot humbly to addres to the King Your Royal Rh

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Rh Father an Account of the Greenland Miion's Beginning and Propagation, which his Majety with o glorious a Zeal protects and encourages; o likewie, with the ame mot humble Submiion, I preume to offer to Your mot Serene Royal Highnes this preent Survey, or Natural Hitory of Greenland; endeavouring by this means to ininuate and recommend to Your Royal Highnes's Favour and Protection, o pious an Under- taking;

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Rh taking; becaue the poor Greenlanders have a Right to claim your Protection, as well as the Kingdoms of Denmark and Norway; and are in Hopes of enjoying, one Day, the greatet Bleings under Your happy Reign.

This little Work cannot fail of a gracious Reception from Your Royal Highnes, as it aims only at, and is calculated for, the Honour of God, and Your Royal Family's Exaltation. The lat of which Rh

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Rh to direct the eyes upon a point at any given distance there must be a stronger convergence of the eyes, and a greater demand upon, the action of the internal recti muscles,, than in emmetropia.

In addition to this, the abnormal shape of the myopic eye impedes its movements. While the nearly spherical emmetropic eye plays like a ball-and-socket joint in the capsule of Tenon, the myopic eye, on account of its elliptical shape, meets with considerable resistance to all lateral rotation, restricting the movement both outward and inward. But while a slight turning of the head may take the place of a rotation of the eye outward, no such compensation is possible when it is desired to turn both eyes simultaneously toward the median line. This difficulty of convergence is the reason that in high degrees of myopia binocular vision for near objects is relinquished, especially when the myopia or the acuity of vision of the two eyes does not correspond. For reading, etc., the best eye only is then used, while the axis of vision of the other eye is not directed upon the point fixed, but has a direction relatively or absolutely divergent. The inconveniences of diplopia, which one would expect under these circumstances, do not generally occur, because the attention is directed only upon the distinct retinal images in the one eye, while the retinal images of distant objects in the other eye being diffuse and indistinct, are readily neglected.

The relinquishment of binocular vision under these circumstances is to be regarded as an advantage. These myopes do exactly what we would advise them to; they avoid all straining of accommodation and strong convergence of the visual axes, and for the most part, too, the bent-over position of the head, since they, at least when reading, are accustomed to hold the book vertically and the head erect. This insufficient movement of the eyes is to be distinguished from an insufficiency of the muscles, of which we have yet to speak.

Other and very important functional disturbances are caused by the distention of the membranes in high degrees of myopia. In the first place, the distention of the retina causes a separation of the perceptive retinal elements; this, in high degrees of myopia, causes a diminution in the acuteness of vision. Nevertheless, myopes do not generally complain of this. Since they can hold objects nearer the eye, they use a larger visual angle, and can


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44 COMPLICATIONS IN MYOPIA. therefore often read fine print easily, although for distance and with concave glasses a diminution of normal vision to one-half or one-third is already evident.

This form of amblyopia is to be distinguished from a diminu- tion of vision which, in high degrees of myopia, often occurs as one of the symptoms of a retinal irritation. The stretching which the retina and other membranes suifer in the myopic eye is prob- ably the cause of this irritation. Aside from the diminution of vision in such cases, there are speedy fatigue in Avorking and a feel- ing of fulness and tension in the eye; often too the eye is sensitive upon light pressure ; besides this there is dazzling, subjective per- ception of light and troublesome myodesopia. The latter is often the principal inconvenience which myopes complain of; the mate- rial cause of this is always small elements in the vitreous, which are also present and visible in perfectly normal eyes. In eyes not myopic these "mouches volantes" are principally noticed when there are upon the retina no distinct images other than those cast by these elements of the vitreous, — that is, when the gaze is directed upon a uniform surface. Hence myopes not unfrequently find relief from this inconvenience in the use of concave glasses, which do away with the uniform indistinctness of their retinal images.

On the other hand, it is probable that in many cases of myopia the myodesopia is actually caused by microscopic opacities in the vitreous, since a cloudiness often develops there which is ophthal- moscopically visible. The presence of such opacities is the rule with those wide-spread choroidal changes which accompany high degrees of myopia in the latter half of life., The vitreous appears fluid and presents under the microscope small opacities, which, without possessing any determinate structure, present a fibrous, granular appearance. These are either fixed by threads which run off and end in the sound vitreous tissue, and in this case are sit- uated generally not far from the disc, or they are freely movable in the fluid substance, and swim about here and there with every movement of the head. Under these circumstances there is often also a circumscribed cloudiness at the posterior pole of the lens (cataracta polaris posterior).

In high degrees of myopia, especially in advanced age, other changes of undoubted inflammatory nature are added to the consec- utive choroidal atrophy ; they are principally in the region of the


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Rh equator and about the posterior pole. In the former position they appear oftenest in the under part of the choroid, in the form of round spots which sometimes, through loss of color and atrophy, are bright red or white, sometimes are noticeable from the dark coloring of the choroidal epithelium; both appearances may be combined, presenting bright spots with black edges. On account of their peripheral position they do not cause much disturbance of vision; they are, however, symptomatic of a predisposition to serious disease.

The changes about the posterior pole of the eye are more frequent. The originally crescentic or annular choroidal atrophy surrounding the disc loses its regular boundaries and spreads irregularly, mostly in the temporal direction.

Insular atrophied spots appear in the neighborhood, and finally coalesce with the principal one. Black, irregular spots, formed evidently of groups of changed choroidal epithelium, often appear upon the white background.

The increase in size of Mariotte's blind spot, under these circumstances, ought scarcely ever to cause disturbances of vision, since the inner layer of the retina remains intact, and therefore the conducting power of the nerves from the periphery is not diminished.

On the contrary, affections of the macula lutea, occurring simultaneously with the above-mentioned changes, or even independent of them, give rise to very serious disturbances of vision. At first, even in eyes whose vision has not yet suffered, there appear a number of irregular bright lines of perhaps the breadth of the principal retinal vessel, or somewhat broader, and of various lengths. These are, perhaps, consequences of the stretching which in places separates the pigment-cells one from another, or flattens, stretches, and depigments them. If central vision is already essentially affected, we generally find changes of an inflammatory nature in the macula lutea, irregularly diffused pigment changes, collections of black pigment interspersed with bright-red or white spots; or exactly in the centre of the macula lutea there may be a black spot, of about the size of the optic disc; or there may be a larger, bluish, elevated spot, perhaps surrounded by a black ring of pigment and often accompanied by hemorrhages in the neighboring retina.


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46 In rare cases it happens that a sharply defined, small staphyloma develops, independent of the crescentic atrophy surrounding the nerve, and separated from it by healthy choroidal tissue. In one case which I observed there was in the neighborhood of the macula lutea a bright spot with a diameter once-and-a-half or twice that of the disc, with pigment-spots sprinkled over it and surrounded by a black ring; it was evidently excavated and there was a corresponding defect in the field of vision. Streatfeild has described a similar case.

The disturbances of vision which accompany the above-described changes in the region of the macula lutea are dependent partly upon the stretching of the retina in this region, partly upon the mechanical insulation which the layer of rods and cones suffers by reason of changes upon the surface of the choroid, and partly from disease of the retina itself. The patients complain of a trembling of the letters when reading, of irregular curves in the lines, of an oblique position and irregular form of the individual letters, of clouds or dark spots in the centre of the field, or finally of absolute inability to see the point fixed (scotoma centrale).

Donders explains the trembling of the letters, by the presence in the macula lutea of a number of very small defects (scotomata). Now, with the movements of the eye, the image of each individual letter falls first upon some spot in the retina which is sensitive, then upon one insensitive to light, so that it alternately appears and disappears; at the same time, in consequence of the irregular displacement of the layer of rods and cones, the shape of the letters appears changed.

Förster has carefully analyzed the phenomena of metamorphopsia (seeing objects distorted and inclined from their true position), and by the use of a system of parallel lines has shown that in a limited central part of the field of vision the curvatures of the lines are concentric. The metamorphopsia also occurs in distant vision with concave glasses, so that, for instance, the bars in the window-sash appear crooked. The sensibility of the macula lutea appears reduced, so that distinct vision is only possible by intense illumination. At the same time the bright light causes


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COMrLICATIONS IN MYOPIA. 47 an unpleasant dazzling. The retina is quickly fatigued in read- ing, etc.

Upon ophthalmoscopic examination, a black spot appears near the macula lutea, often surrounded by a reddened area (hy}>ersemia or extravasation). Still, F5rster was satisfied that the portion of the retina affected by metamorphopsia was much larger than that in which changes were ophthalmoscopically visible. From the concentric curvature of the lines Forster supposed that the sensitive elements of the retina were crowded by the pathological process toward the centre of the diseased jmrt.*

While the above-mentioned diseases of the macula lutea at least spare the periphery of the field of vision, it happens much oftener in myopic than in previously healthy eyes, that sight is absolutely destroyed by detachment of the retina.

The complication of myopia with glaucoma will be considered under the head of the last-named disease.

A cure for myopia cannot be expected. In the cases of ray- opes who have strained their eyes for weeks or months, one often sees that rest or the use of atropine causes some withdrawal of the far point ; in such cases there has been no change in the con- dition of refraction, but there has been relief to a sjjasm of ac- commodation, which, when discussing hypermetropia, we shall describe as latent accommodation. There is more to be done in avoiding the development of myopia. With this in view, it is all-important to regulate the use of the eyes. Reading, etc., at twilight is to be strictly forbidden; and even with sufficient light, work ujx)n very near objects should not be too steadily pursued. Above all, a strong bending forward of the head is to be avoided. Children with very slight myopia often, in spite of that fact, use persistently an object distance from 4 to 6 inches ; this, of course, involves a strong tension of accommodation, a high degree of convergence and a bowed position of the head. It is the duty of parents and teachers to correct this. If the case is

layer, described by H. Muller. Saemisch (Beitrage zur Anatomic des Auges, 1862) has shown that it also occurs as a circumscribed affection of the macula !utea.
 * An affection which might well cause this is the retinitis of the external


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48 MYOPIA, TREATMENT. not one of simple bad habit, but if in connection with distinct vision there exist a high degree of myopia, for instance, M^, it is at all events advisable to remove the far point by concave glasses to about 16 or 18 inches, and then to enforce an object distance of at least 12 or 14 inches.

To insure an erect position of the head, it is advisable in read- ing to hold the book in the hand, and in writing to use a desk with a steeply-inclined and sufficiently high surface. In furnish- ing school-rooms these points deserve careful attention. It is for the interest of society to combat the development of myopia by a proper system of lighting and furnishing school-rooms.*

If a high degree of myopia appear in early youth, it should influence the choice of an occu])ation. It is difficult, however, to lay down positive rules in this matter.

In most cases it is necessary to render distant vision distinct by the use of proper concave lenses. We have already seen that the concave lens whose focal point corresponds with the far point fulfils this condition, and we shall here only repeat that always only the weakest lenses with which distinct distant vision is pos- sible should be used. The question whether the correcting lenses should also be used for near objects has been much discussed. In this matter a general rule cannot be laid down. The question must be decided for each individual case. A myopic eye, provided with the proper concave lens, behaves exactly as an emmetropic one, which indeed is a desirable condition. Nevertheless, it is only under the following circumstances that the neutralizing concave glasses ought to be worn continuously and used for near objects.

1 . The myopia should not be greater than ^ or ^. For low degrees of myopia, under M2^ there is scarcely ever any neces- sity for wearing concave glasses continuously.

2. The range of accommodation must be normal.

3. Vision must be normal.

4. The continuous use of concave glasses must have been begun in youth.

Under these circumstances, there is no objection to the contin-

dern, nebst Vorschlagen zar Verbesserung der den Augen nachtheiligen Schuleinrichtungen. Leipzig, 18G7, und Deutsche Klinik, 1866, No. T.
 * Compare Dr. H. Colin, Untersuchung der Augen von 10,060 Schulkin-


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MYOPIA, TREATMENT. 49 uous use of neutralizing glasses. Qne often sees myopes who wear their glasses continuously, and with only good effects.

If any one of these four conditions be wanting, we have a contra-indication for the continuous use of neutralizing glasses. A more exact explanation of these conditions belongs with the consideration of tlie above-named contra-indications. The cir- cumstances which make the use of neutralizing concave lenses unadvisable are the following :

1. A high degree of myopia. The continuous use of neutral- izing concave glasses with myopia of a greater degree than ^ is un- advisable, on account of the diminished acuteness of vision which generally co-exists. Even in high degrees of myopia, where circumstances make it necessary to wear spectacles continuously, the patients generally prefer those which do not completely neu- tralize the myopia. A continuous use of such glasses is sometimes impossible even for distant vision. This is perhaps because of the preponderating elongation of the eye in the direction of the visual axis. The sagittal diameter increases relatively more than all the others, so that lenses which correct the myopia for central vision are too strong for all objects in the periphery of the visual field. Under such circumstances it is often best to wear continu- ously spectacles which remove the far point to about 12 inches, and then to employ an auxiliary glass, about — ^2? ^^^ distant vision.

2. Diminution in the range of accommodation. We have already remarked that the myopic eye is naturally adapted to only slight efforts of accommodation, and all straining of accom- modation is regarded as hurtful to it. If now by neutralizing glasses we remove the far point to an infinite distance, we at the same time remove the near point and the whole range of accom- modation away from the eye, and the myope who formerly saw near objects distinctly without accommodation, can now do so only by accommodating. We demand in this case no more from the accommodation than the emmetropic eye does without difficulty ; but we ought first to satisfy ourselves that the accommodation of the myopic eye is able to respond to such a demand without injurious straining. We ought, for instance, never to compel continuous accommodation up to the region of the near point. Myopes who have worn neutralizing glasses from their youtli, are compelled to use weaker ones on account of the gradual with-


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50 MYOPIA, TREATMENT. drawal of the near point, dependent upon advancing age. Pres- byopia develops in myopic as well as in emmetropic eyes. At the same time of life when the erametrope begins to need convex glasses the neutralizing concave glasses become too strong for the myope to use on near objects.

3. Generally the use of concave lenses is contra-indicated if from any cause the acuteness of vision is noticeably diminished. Corneal opacities or irregular astigmatism, cloudiness of the lens or vitreous, and all the causes of amblyopia, which oc«ur so frequently in high degrees of myopia, and are due to retinal or choroidal changes, contra-indicate the use of concave lenses. For distance, littlfe is usually gained by the correction of the myopia, and for near objects the hurtful influence of the concave lenses is to be feared, since the patients, in spite of them, approach closely to objects in order to obtain as large retinal images as possible, and then they must employ a tension of accommodation so much the stronger. To abstain as much as possible from work is the only advice to be given under these circumstances, as the causes of the amblyopia cannot be removed.

4. Finally, with reference to the relative range of accommoda- tion, the use of concave lenses ought not to be begun too late. Myopes not only acquire the habit of converging to the near point without accommodating, but also within the range of their distinct vision they associate with every degree of convergence of the visual axes only a relatively slight degree of accommoda- tion. Now, upon providing the eyes with concave lenses not only is the entire range of accommodation removed farther from the eye, but the position of the relative range of accommodation is also changed. Youthful eyes can generally accommodate them- selves to these changed conditions ; or where this is the only dif- ficulty, one can begin with weak lenses and proceed gradually to the neutralizing ones. At advanced age, however, myopes cannot, so easily as emmetropes, change the position of their rel- ative range of accommodation. The greater demand upon the available accommodation in near vision with concave glasses is generally very uncomfortable, and causes quick fatigue of accom- modation.

It is, moreover, probably because of the changed position in the relative range of accommodation that myopes who are accus-