and a little to one side of the visual axis, sometimes having a splendid disc resembling the tapetum of the sheep, or the coloured choroid of fish; but more usually occupying a circumscribed annular space, and is seen only in a strong light, and in a particular direction. The causes of this point are involved in obscurity. However, it is by no means a constant appearance in amaurosis, nor is it incompatible with useful vision.

"In the amaurosis from inflammation of the choroid or retina, where the diseased action has entirely subsided, the veins of the conjunctiva are varicose, the iris is discoloured, thick, tough, inelastic, and preternaturally vascular; the substance of the crystalline is more or less absorbed, or converted into a fluid, and discoloured; the vitreous humour is opaque and of a deep yellow colour. The retina, like the other transparent textures, becomes opaque under inflammation, and it is probable that under these circumstances, adhesive matter is effused upon the interior of the choroid; this supposition I have never had an opportunity of verifying by dissection, in cases of which the history was known." 150.

Our author here relates two curious cases; one of absorption of the vitreous humour and collapse of the retina; the other of amaurosis, from cerebral tumour. Many cases of amaurosis from concussion have fallen under the inspection of Mr. Travers; and also of congenital organic amaurosis, for which we must refer to page 152 et seq.

At page 155 Mr. Travers takes up the subject of functional amaurosis, which he divides into three species, viz. Imo. the symptomatic, or that which is merely a symptom of of some general disease, or disordered state of the system, as of general plethora, general debility, &c. 2ndo. The metastastic, produced by sudden transference of morbid action. from another organ of the body, as from the skin, testicle, &c. 3tio. The proper, depending on a peculiar condition of the retina, as visus nebulosus, muscæ volitantes, &c.

Symptomatic Species. This, like nervous deafness, sometimes follows typhus, scarlet fever, infantile fever, and other acute constitutional diseases. It is sometimes a consequence of chronic wasting diseases, in which organic changes interrupt the nutrition of the system. Mr. Travers has seen a rapid and severe salivation, instituted for a remote affection, produce gutta serena of both eyes. The state of the circulation has a marked influence upon imperfect amaurosis, as well as upon nervous deafness. Mr. T. knows patients whose vision is benefited in a high degree, and others in whom it is as much deteriorated by the quickened circulation of a full meal and a few glasses of wine. The former,

as may naturally be supposed, are spare and meagre ; the latter plethoric. Of the mental emotions, grief appears to be most influential in producing symptomatic amaurosis. This affection is often seen in young widows. The amaurosis lactantium, in which the infant preys upon its mother, exhibits a familiar example of the disease from constitutional debility.

"Amaurosis depending on vascular congestion is marked by some or all of the following symptoms, viz. dilated and sluggish or immoveable pupil, ptosis, or strabismus, and oblique or double vision of the affected eye; a preternatural action of the carotids, flushed face, sense of weight, pain, or stricture of the scalp, lethargy, occasional tinnitus aurium, with greatly disordered and irritable stomach. The patient frequently complains, particularly in straining, stooping, or on first lying down, of seeing luminous sparks or flashes, and a reflection of one or more of the choroidal vessels, the visible pulsation of which is a cause of much distress to him. A person thus affected accurately described to me the zona minor iridis, as distinctly presented to his view."

158.

Undue determination of blood to the head often exists independent of general plethora, "and is aggravated by loss of blood," of which Mr. Travers relates an example in the person of a young medical gentleman, who came to him. from the country in extreme anxiety, and solicited him to apply a ligature to the carotid artery. This gentleman was of short stature, and constitutionally healthy. His pupils were large, his countenance suffused, and bearing the appearance of preternatural determination of blood to the head. He had had two inflammatory attacks in the April and October of the same year; during which, he had lost upwards of an hundred ounces of blood. He had now a constant heavy pain in the head, chiefly over the coronal suture, and in the direction of the sinuses, with tinnitus of the left ear.

"After stooping, the giddiness was extreme, and a golden-coloured spot, edged with black, appeared floating before the eye. He had been troubled with muscæ in excess, for a year and a half past; he had now fire sparks flashing before the sight, and saw a pulse in the choroid synchronous with that of the wrist. When looking at near objects he was not troubled with muscæ, but they were always numerous, in proportion as the object was remote. He did not complain of much dimness. His complaints were not relieved by topical blood-letting. He recovered gradually, but perfectly, under a regulated diet, and a course of the blue pill with saline aperients." P. 160.

The amaurosis from depletion is sometimes mistaken for that from plethoric congestion, owing to the coincidence of

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a dilated and immoveable pupil, muscæ, and a deep-seated pain in the head, with occasional vertigo, together with its occurrence often in corpulent habits. It supervenes somewhat abruptly on uterine floodings, and large and sudden depletion for acute diseases. The pain is not confined to the region of the orbit, but is that peculiar nervous pain to which women are subject after uterine hæmorrhage, attended with a sense of defined pressure, as of an iron finger on the brain," and sometimes a distressing jarring noise, like that of a mill or threshing-floor. "By a cautious use of tonics it is relieved-by whatever lowers or stimulates, whether diet or medicine, it is decidedly aggravated." The vision, in this form of amaurosis, our author observes, is further enfeebled by the loss of as much blood as flows from two or three leech-bites. This, he avers, is not imaginary. He has seen distinctly marked cases of it," in which large and copious venesection was still urged as the only resource of art." This he considers to be a fatal mistake. We have seen several cases where local congestions of blood in the head, lungs, and other organs, appeared to depend on some peculiar state of the system, which caused the blood to concentrate in these parts, while some other parts were deficient of the proper quantity. Here neither general nor local depletion did good. But we have seen decided advantage from revulsive measures, quietude, and regulated regimen. For amaurosis sympathetic of irritable conjunctiva, we must refer to page 161 of the volume itself.

Metastatic Species. Mr. Travers has seen this species of amaurosis from the state threatening effusion into the chest-from gout in the foot-swelled testicle; in all which cases the oppressed organ was as suddenly relieved as the eye was affected. "Thus a person goes to bed with good vision, and rises blind." Here our author relates cases in

illustration.

The gout attacks the eye through the medium of the stomach; vomiting occurring, with gastric pain, on the subsidence of inflammation in the extremities, succeeded by violent headach, with sudden and permanent loss of sight. To this class also belong the cases of amaurosis consequent upon the sudden suspension of the catamenia, or habitual hæmorrhoidal discharges-the rapid healing of large ulcers -the sudden retrocession of cutaneous eruptions.

Amaurosis proper. The following case will best explain a temporary palsy of the retina from over excitement. It is given in the words of a young gentleman ardently engaged in the study of the profession when thus interrupted.

"Having habituated myself for the preceding twelve months to intense study, reading and writing to a very late hour, which had been only interrupted for a few days by a slight inflammation of my right eye, I quitted London to recruit my health in the pure air of This daily improved, but I found a growing imperfection in the vision of my left eye, which advanced unaccompanied by inflammation, pain, or any other external symptom of disease. It seemed at first a film before the sight, but at length amounted to a total loss of vision. On examination, I found the pupil greatly dilated, and learned that the iris had little or no action. By the advice of Mr. T. whom I now consulted, I applied a blister, extending from the centre of the forehead round the eye to the root of the nose. This drew well, and I continued it open for ten days, closing the eye from light during that period. I took at the same time a calomel and opium pill thrice a day. In the space of a few days my mouth became sore; the pupil acted, though unequally, and I experienced a gradual recovery of vision. In the course of six weeks I was enabled to resume my studies, and could perceive no defect of vision. I had gradually reduced the dose of calomel, and now discontinued it, drinking the decoction of sarsaparilla. At the distance of four months from this occurrence, the pupil is regular and active, and the sight unimpaired.' " 165.

Symptoms of Amaurosis. Pain in the head and temples is a precursory symptom of amaurosis, diminishing as the dimness increases, and usually ceasing altogether when the amaurosis is complete. If, however, the pain be severe, remitting imperfectly, and increased by exercise, whether diffused or circumscribed in extent, it is usually connected with an organic cerebral change. In this case, derangement and torpor of the primæ viæ, loss of strength and flesh, disposition to stupor, occasional confusion of intellect, inaptitude to exertion, and paralysis of one or more muscles, will be concomitant symptoms.

"There is an intermittent spasmodic pain accompanying some cases of amaurosis, shooting through the orbit into the head, of the most acute and distressing severity; it makes a periodic attack at or about the same hour, every night, or every second night, and continues for several hours; it is accompanied with convulsive quivering of the muscles of the eye and eyelids, and profuse lacrymation; there is nothing in the appearance of the organ to explain its nature and origin.' 168.

Mr. Travers believes it to be a tic douloureux affecting one or more of the orbitar branches of the fifth pair of nerves. He has cured two cases by arsenic, where opium failed to prevent the paroxysm. Paralysis of different muscles, as the levator palpebrarum, orbicularis, &c.-vertigo-ptosisloss of association and direction-and strabismus, are all Vol. II. No. 5

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more or less symptomatic of amaurosis, and on each of these our author makes acute and interesting observations. The same may be said of Mr. Travers's remarks on hemiopsiadistorted position of objects, and muscæ fixed or floating. When these last are fixed, they usually belong to organic amaurosis-when floating, to functional sympathetic or proper amaurosis. In the fixed musca, the opaque spot varies in density, in different individuals, "and under a long but gentle mercurial course, I have known it become considerably less dense, so as not to intercept bright light."

The musca volitans is sometimes solitary; but more frequently an immense assemblage, descending in a cloud as the eye is raised, and ascending as it is depressed. The patient's attention being minutely directed to these spectra, they are curiously and minutely described.

"Almost every person has, at some time or other, seen these appearances, but especially those subject to dyspepsia, and disordered function of the stomach and liver. At the moment of approaching deliquium, they appear in one vast cloud, and they are harbingers of the intense bilious headach. At the instant of their appearance, the sentient extremities upon the fingers and tongue are so benumbed, that objects of touch and taste convey a very indistinct impression, as if some muffle were interposed. These sensations I am describing ad vivum, for I was formerly often the subject of this attack, which was followed by a certain degree of confusion of intellect, and temporary suspension of memory, so as greatly to embarrass, if not to take away the power of intelligible expression. I mention these opposite and transitory states of emptiness and plethora concomitant with the floating muscæ, to show the purely functional origin of the affection. The one (deliquium) is an uninjected, the other (sick headach) an over-injected or congested state of the nervous texture; or suspension from vacuity, and suspension from plethora. An analogy is plainly to be perceived between the corresponding states of the sentient and visual extremities, described in the last affection, to that of a temporary incomplete paralysis." 177.

Coloured spectra, or luminous impressions of objects remaining upon the retina, are usually preceded by the fixed. muscæ, and may then be regarded as a more advanced stage of the complaint, though sometimes Mr. T. has known them to be symptoms of functional derangement, and to disappear as the vision recovered. For a very curious and interesting case in illustration, we refer to pages 179-30-81, of the work.

A very frequent and characteristic symptom of functional amaurosis, our author observes, is a thin mist, fog, smoke, or gauze, which takes off the acies oculorum acer. Thus the letters of a book run together, and the outline of all