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composed state. Several tons of excellent copperas have already been made, and it is supposed, the works will yield, the ensuing year, from 2 to 300 tons of this valuable article. Attempts are also about to be made at Winthrop, in the District of Maine, to manufacture this salt from an aluminous schistus, containing a considerable quantity of sulphuret of iron, in a partly decomposed state.

A labouring man near Plymouth had long been afflicted with hydrocele of the Tunica vaginalis, for which no remedy had been applied, and the tumour was of a large size. While he was standing near a vicious horse, the animal being irritated, seized the patient by the scrotum with his teeth, in such manner as to penetrate both the integuments and vaginal coat, by which the contents were immediately evacuated. A severe inflammation ensued, and a radical cure was the happy result.

The following gentlemen were examined and licensed as practitioners of medicine at the February meeting of the Censors of the Massachusetts Medical Society :-Ephraim Buck of Woburn; Paul L. Nichols of Freeport; Usher Parsons of Alfred, and Silas West of Tisbury.

Royal Society.

Nov. 28, and Dec. 5.-The conclusion of Mr. Brande's researches on the blood was read. The result of the author's experiments is, that very little iron exists in the blood; that the quantity is so small as to render it very improbable that the colour of that fluid depends on it; and that its influence is much less than has been supposed.

Dec. 19. The first part of a paper by Dr. Herschell on the Comet, was read. Dr. H. noticed something like a distinct luminous body about the centre of the nucleus, which changed its relative position, sometimes appearing nearer, at others further, from the side next the sun; and differing, under these circumstances, very much in brilliancy. From these facts he was led

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to infer, that the comet enveloped a real planetary body; and after a series of observations, on the 16th of October, when the comet was 114 millions of miles from the earth, he ascertained that this body was 428 miles in diameter, and surrounded with a cometic atmosphere. For this purpose he viewed it with seven, ten, and twenty feet telescopes, containing magnifiers of various powers, from 40 to 600 times.

Jan. 9th, and 16th.-The conclusion of Dr. Herchell's paper on the late comet, entered into a very minute investigation of the nature and extent of the luminous matter which surrounded it at some distance from the planetary body in its centre. This matter the doctor supposes to be of a phosphoric nature, The length of the tail he estimates to be, at the end of October, about 100 millions of miles; but to be very variable in length and breadth, and a hollow cone, emitting light on all sides. The inner side he supposes may illumine the planetary body in a manner similar to that in which the ring does Saturn. From the great alterations which took place in the nature and dimensions of the tail, he is inclined to conjecture that comets may be formed of nebulæ; that those nebulæ undergo condensation in their approach to the sun, or to some of what are called the fixed stars; and that in process of time they may become regular planets. On contrasting the appearance of the late comet with that of 1807, he is inclined to suppose that of 1811 much younger than the former.

Jan. 23d.-Mr. Davy communicated a paper written by Mr. Campion, on the structure of the eye of man and birds, particularly in relation to that faculty which enables it to adjust its focus to the distance of the object. The author examines the different conjectures and theories which have been proposed to account for this circumstance, and explains how the eye can have perfect images of objects at very different distances. It has been generally agreed that the eye must have some contractile power; but the existence of any organ capable of such a function, has never been ascertained.

Mr. C. on examining the eye of an eagle, discovered the existence of a small muscle attached to the sclerotica, and capable of contracting the eye, in a manner equal to effect the ne

cessary change in the focal distance. The same muscle he discovered in some other birds, and hence he inferred that something analogous exists in the human eye. He observes, that images pass before the eyes of maniacs as vividly and distinctly without any sensible objects, as they do over those of some persons from objects within the focal distance of their eyes.

Medical and Physical Journal of Feb. and March, 1812.

Imperial Institute.

In our history of the last year, in speaking of the researches on the action of the eight pair of nerves on respiration, we have attended to the important experiments by which M. Legallois, physician in Paris, has proved that very young animals are capable of living without breathing during a time, by so much the longer as they are nearer to the period of birth.

M. Legallois having caused very young animals to undergo other lesions, has obtained still more singular results, which have finished by conducting him to the resolution of a question debated by anatomists for near two centuries; that of the influence of the nerves on the motions of the heart.

Having decapitated some of these animals, he observed that their heads continued to give signs of life precisely during the same time for each age that animals of this age are capable of living without breathing; from which he concluded that these heads die only for want of the respiratory function.

It is known besides from the experiments of Fontana, that it is possible to prolong life in the decapitated trunk by blowing air into the lungs. The immediate principle of the life of the trunk is therefore in the trunk itself.

Now we know on the other hand, that the life of each part requires its immediate communication with the spinal marrow, by means of the nerves, and a free circulation of the blood in the portion of the medulla, which furnishes nerves to this part.

This being settled, we should suppose that the simple destruction of a portion of the spinal marrow ought to affect those parts only to which this medulla gives nerves; but it happened ⚫therwise in the experiments of M. Legallois. The destruction

of a portion of the medulla quickly killed the whole body, and produced, of course, more effect than even decapitation.

M. Legallois, in examining attentively all the circumstances of this phenomenon perceived that this lesion soon enfeebled and arrested the circulation, that the arteries emptied themselves, &c. He concluded from it that it killed mediately, and by weakening the motions of the heart.

He verified this conjecture by experiments, whose success may seem yet more singular than the first phenomenon. By diminishing, by the ligature of arteries, or even by amputation, the number of parts which the heart must supply with blood, the power that remains is rendered adequate because fewer efforts are left it to make, and the lesion of the medulla is less quickly mortal; thus an animal whose head has been cut off, will afterwards perish less quickly by the lesion of the medulla than if the head had been left on; and as, at the end of some time a partial lesion of the medulla much diminishes the circulation in the parts to which the destroyed portion of the medulla gives nerves, the destruction of a portion of the medulla affords a facility of destroying another portion of it after some time, with out causing death so quickly. Thus, when the head of an animal is cut off, it is more easy to destroy the cervical medulla without killing the rest of its trunk; and, when its cervical medulla is destroyed it is more easy to do this operation on its dorsal medulla; so that one might cause each layer of its body to live successively, if the heart and lungs could be transported thither, and, that the chest, which contains these organs, should long preserve its life without the concurrence of any of the other parts.

The general and direct result of this fine series of experiments, is that the motion of the heart depends on the whole of the spinal marrow, which exerts its influence on it through the medium of the great sympathetic nerve and in this way we explain how the heart is affected by the passions, without immediately depending on the brain; and we succeed in submitting to the empire of the nerves the only one of the muscular organs in which the nervous action was subject to difficulties; finally, as the removal of the brain does not affect the mo

tions of the heart, while that of the medulla destroys them, the opinion advanced for some years by great physiologists, that the brain is not the only source of the nervous action, but that each part of the nervous system takes also a part in this action, is fully confirmed.

Analyse des travaux de l'institut impérial, pendant l'année, 1811.

M. CHAUSSIER, correspondent and professor of the faculty of medicine, has communicated a memoir on the dangerous disease called puerperal fever, or peritonitis. Physicians have thought it was produced by a milky effusion, because a serous fluid mixed with flakes like a caseous substance has been found in the abdomen. M. Chaussier has proved that these appearances are false: he cites examples of a similar disease, which attacks men and young girls; he shews that it is a catarrhal disease; he afterwards explains how the changes of constitution from pregnancy and parturition expose to it; and what is more important, he announces having obtained the most marked success from the employment of vapour baths and frictions of mercurial ointment on the abdomen.

Ib.

The use of vapour baths as a local and general application is becoming very prevalent in England. It is said that "inveterate catarrhs, chronic rheumatism, contraction of the muscles, and stiff joints, yield to the influence of the vapour." Gout, calculi, and tooth-ache, are also cured by it. In the petechial fever of this country they have been undoubtedly beneficial; though applied in rather a coarse way. The common practice has been to immerse billets of wood in hot water for some time, and afterwards to place them in the patient's bed.

White Hellebore.

MR. MOORE'S Conjecture respecting the composition of the Eau Medicinale d'Husson* is admitted as highly probable by the

* See Review in last number of this work, page 97.