portance, and as I have had an opportunity of observing very beneficial effects from the internal exhibition of mercury in several cases, it may be proper here to mention them.

In two of these cases the great toe was affected, in other two the disease appeared in the fingers. In all of them it had continued a considerable time, and in one of those where the finger was affected, there was often a profuse hemorrhage from the ulcer. Mercury was given in small doses at first, and gradually increased, so as in twelve or fourteen days sensibly to affect the gums.

The sores in general soon assumed a healing appearance after the system was in this state, and the bulbous swelling of the joint gradually subsided. The ulcers were dressed with wax-ointment, so that the effects of the mercury might be watched, and after the sore began to heal, a weak solution of the muriate of mercury and escharotics were occasionally used to clean the wound or keep down any fungus. The mercury was continued till the ulcers were perfectly healed, and, as is generally advisable under such circumstances, it was taken in smaller quantities for some time after the patients were apparently cured.

How far this treatment may be found successful in all cases of this disease, can only be determined after considerable experience. I am persuaded, however, that there are `cases wherein it will be found an efficacious remedy.

III. Of Corns.

The great relief which corn-cutters give by simply removing the thickened and hardened cuticle, must have prevented medical men from making any inquiries into the nature or particular treatment of this disease; and whilst it escaped the notice of the latter, it could not have been a desideratum of the former, that, any mode of treatment should be found out which might make their operations less useful, or more seldom

necessary.

If a corn be examined, it will be found to consist of an increase in the thickness of the cuticle of the affected part; which, by acquiring firmness and hardness, presses on the tender skin underneath, thus exciting pain and inflammation:

The portion of diseased cuticle is thickest at the central part of the corn, and forms a conical point, which makes a corresponding concavity in the corn underneath. The inflammation sometimes terminates in suppuration, and the distress which is thus occasionally produced, exceeds what might be supposed to arise from a disease which is at its commencement so trifling.

When all the hard parts are removed, and some slight defence giving to the newly exposed and tender parts by the application of adhesive plaster, great relief is obtained; but it is only temporary. A new growth of hard cuticle quickly succeeds, which renders it soon necessary to recur to the same means; and these must be employed more or less frequently during the remainder of life.

From the great analogy of corns to the common wart, a disease so successfully removed by the application of escharotics, it seemed by no means improbable that a similar practice might be efficacious in the cure of corns. Accordingly I embraced the first opportunity of putting it to the test of experience.

After removing the external layers of a corn, I rubbed the surface, previously moistened, with lunar caustic. In a few days the contiguous parts lost all their tenderness, of which there had been a considerable degree, and the hardness was diminished. By a second application of the caustic the hardness disappeared, and a corn, which before required to be cut every few weeks, was, by two or three subsequent applications, kept from growing and exciting any uneasiness for several

years.

Soon after this case occurred, the efficacy of the practice was strikingly exemplified by the application of the muriate of mercury to a corn. A patient who had several warts on the prepuce, to remove which he had tried various applications, at last came under my care; and I used, with success, the application of a saturated solution of the muriate of mercury in spirit of wine. Being at the same time much troubled with corns, and struck with the similarity of the two diseases, he thought he might try if the solution, which was so useful in removing the warts, would be as effectual in curing the corns.

He made the experiment, and met with the success he had anticipated.

From the frequency of the disease I have had many opportunities of recommending this practice, and I believe it has been universally followed with results equally successful. It is a remedy which, under no circumstances, can do harm, and those who have this troublesome complaint can easily receive such instructions as on all occasions to apply it themselves. I have generally directed them to cut off, with a sharp knife, or to tear out as much of the corn as they could do with safety: to keep the toe immersed for some time in warm water; and after drying all the skin contiguous to the disease, to rub over carefully all the surface of the corn with the caustic, or wet it with the solution of muriate of mercury, by means of a camel's hair pencil. Either of these applications, two or three times repeated after each of the eschars have separated, will in most instances be found sufficient to remove the corn; and when at any future period it has a tendency to grow again, the application of the caustic may be safely renewed.

§ IV. Of the Treatment of Chilblain.

There are many people in this country who suffer a great deal from chilblain, though it seldom occurs in the aggravated form which it so often assumes in more northern climates. It generally appears as an inflammation of a portion of the skin of some part of the extremities, and most frequently affects the heel and toes or outer edge of the foot. The redness is of a leaden hue, accompanied with swelling and an intolerable itchiness.

Though I am aware that stimulants are usually employed and are found useful in the treatment of this stage of Pernio, yet, as I have had opportunities of observing such remarkable benefit from the application of diluted tincture of cantharides, it may be worth while to mention in this place the effects and the mode of using this medicine.

One part of the common tincture of cantharides to six parts of the soap-liniment, is the form which I have found to answer; and it has seldom been found necessary to vary the

proportion of the medicine. The affected part of the skin is to be well rubbed once or twice a day with this embrocation, and afterwards kept warm. One or two applications usually remove all the itchiness, and after a few days the swelling and redness completely subside. As I have used this application in such a number of cases, and as it has been found equally successful in the practice of others, I have no hesitation in recommending it as a most useful and valuable remedy.

In the second stage of the disease, when vesications have formed on the skin, and ulceration has taken place, the cantharides will be found a beneficial application to the inflamed skin contiguous to the ulceration: it has a powerful effect in diminishing the swelling and thickening of the parts, which so often remain after frequent attacks of this disease. There is no application so useful to the ulcer itself as the common ointment composed of the red oxide of mercury.

Further Observations on the Cataract, by BENJAMIN TRAVERS, Esq.; Demonstrator of Anatomy at Guy's Hospital; Surgeon to the Hon. East India Company; and to the London Infirmary, for Diseases of the Eye.

[From the London Medico-Chirurgical Transactions, vol. V.]

In the paper which I had last year the honour of reading to the society, I attempted to convey an idea of certain appearances by which the various textures of cataracts might be distinguished, and which appeared to me to afford juster indications than could otherwise be obtained, of the modes of operation which they respectively require. The present communication contains the further results of my observation on this subject.

The classification of the different species of lenticular cataract which I have ventured to suggest, is to be understood as general, comprehending of course their intermediate degrees of consistency. The fluid cataract, for example, upon rending

its capsule, is sometimes readily diffused in the aqueous humour, so as to render it uniformly milky-at other times it is viscid and oily, and sinks to the bottom of the chamber, resembling the onyx of lymph or pus in appearance. The gradations of consistency between this and the state of flocculency are less obvious, although their existence is not less certain. The caseous species comprehends, under the description of its characters formerly given, a range of considerable extent, from the softness of the flocculent to a degree of firmness approaching that of the hard cataract. The former has the permeability to the needle and the facility of dissolution of the flocculent cataract, without its symmetrical, or its fanciful cloud-like arrangement; the latter has a gum-like tenacity and incompressibility, upon which the needle makes but a superficial impression, and which renders it incapable of a change of figure, although it wants the colour and seeming compactness of that which I have denominated "the hard cataract." These therefore I have regarded as the extremes of the caseous species. The appearances which they present differ according to the density of the opacity, which depends on their respective volume and texture. The best marks of discrimination, with which I am acquainted, are a uniform bright or luminous whiteness, and looseness or sponginess of texture, as indicating softness; and a dull white or bluish grey tint with a more condensed and less voluminous texture, the opposite state. There is an appearance of radii, corresponding to the segments into which the lens separates by maceration or compression, characteristic of the firm caseous cataract. These radii look like membranous bands passing at equal distances from the centre to the circumference of the lens. They are sometimes faintly marked, but always distinguishable, when present, from their superficial and glistening appearance. They are hence generally supposed to be capsular, but the capsule is uniformly transparent, and the cataract firm.

That a practical value attaches to these distinctions in selecting, and in the mode of conducting the operation, may be easily shewn, and my more matured experience has fully convinced me of their importance. In those of the fluid and flocculent character the diversity is insufficient to influence the mode of operating, and probably too minute to be ascertained by