§ III. NATURAL HISTORY, &c.

1. MECHANISM OF THE HUMAN VOICE IN SINGING.

A memoir on this curious subject has been read to the Academy of Sciences by M. Bennati, and examined by MM. Cuvier, Prony, and Savart. The former of these three philosophers has reported thereon to the Academy. The principal object of the memoir is to make known the powers of an organ in effecting the modulations of the voice, which in this point of view has been little attended to by physiologists. This is the soft palate, or the narrow part of the gullet formed above by the uvula, at the sides by the arches, and at the bottom by the root of the tongue. M. Bennati has succeeded in constructing an instrument which can include three octaves. He points out in his memoir the precautions which should be taken in this respect for the instruction of young persons destined to be vocalists; amongst one of the principles, is, to interrupt the exercises at the period when the voice changes. M. Bennati concludes his memoir by this proposition, that it is not only the muscles of the larynx which serve to modulate the sounds, but also those of the os hyoides, of the tongue, and of the veil of the palate; without which all the degrees of modulation necessary in singing cannot be attained. From hence it results that the organ of voice is an organ sui generis, an instrument inimitable by art, because the materials of its mechanism are not at our disposal, and we cannot conceive how they are appropriated to the kind of sonorousness which they produce. This result, although not entirely new to science, appears to the reporters to be proved by M. Bennati by new facts and observations, and to have acquired such development as to fix the attention of physiologists*.

2. GLOBULES IN THE HUMOURS OF THE EYE.

MM. Ribes and Donne have lately discovered globules in the humours of the eye, of a smaller size than those of the blood. There are three orders of them: the first are in sinuous chaplets, and very apparent; the second are isolated, larger than the others, aud surrounded by a black circle; the third are least distinct, and resemble a kind of mist. The authors are disposed to question the utility of so many parts of the visual organ in the production of impressions on the retina. It is known that the removal of the crystalline lens by extraction does not destroy vision. The rays of light must be considerably modified by the globules of the humours t.

*Revue Ency. xlvi. 502.

† Archiv. General. Medical Journal, v. 148.

3. USE OF NITROGEN IN RESPIRATION-CYANOGEN IN THE BLOOD. Dr. Rich, Professor of Chemistry in the Vermont Academy of Medicine, has put forth a view of the part which nitrogen performs in respiration, to produce cyanogen, which then exists in the blood as cyanide of iron. He quotes the observations of others, by which the nitrogen of the atmosphere is shewn to be absorbed in respiration, and also occasionally given out again in the lungs, and he thinks there is no more difficulty in conceiving that it should enter into the blood in the pulmonary vessels, and combine with the carbon in the blood, just as oxygen does. Cyanogen would probably result; and then, referring to the ordinary processes by which Prussian blue is obtained from dried blood, Dr. Rich seems to consider it just as likely that the process should merely transfer the cyanogen already existing, as that they should cause its formation from the carbon and nitrogen present. This view appears to him to explain the difference which has existed amongst chemists relative to the presence of iron in the blood. Englehart's process of detecting iron in the fluid blood, or rather in the colouring matter of the blood, namely, by passing chlorine through it for a time, and then testing the clear solution, he conceives to depend upon the chlorine taking away the cyanogen from the iron, and so bringing the latter into a state indicative by the usual tests *.

Dr. Rich has not had the opportunity of supporting his views by any experiment, although he suggests some. We cannot help observing that the idea of the cyanogen obtained by the Prussian blue maker being merely that which pre-existed in the blood, appears to be a very violent one. The quantity he can obtain from dry blood is enormous, many times surpassing the weight of the colouring matter in it. Further, the colourless serum will yield plenty; and now, in fact, blood is but seldom resorted to for it, but hoofs, horns, and other sources of animal matter, are used for the purpose.

4. ACTION OF THE PILE ON LIVING ANIMAL SUBSTANCES.

Being desirous of testing by experiment the opinion often entertained and advanced, that secretions in the living body are the result of electrical decomposition, M. C. Matteucci applied the poles of a voltaic pile containing fifteen pairs of plates, to two wounds made on the lateral parts of the abdomen of a rabbit, so as to leave the peritoneum bare. The poles were of gold, and it was soon found that a yellow alkaline liquor, containing many bubbles of air, collected at the negative pole, whilst a yellow liquid with few bubbles and slightly acid, collected at the positive pole. When the positive pole was copper, it became covered with a green coat slightly acid; the same results were obtained by acting upon other parts of the

*Silliman's Journal, xviii. 52.

body, as the liver, intestines, &c. The substance obtained at the negative pole besides alkali, contained much albumen and coagulated by heat; the fluid at the positive pole also contained a highly azotated substance.

These experiments M. Matteucci considers as supporting the opinion advanced above; and considering the secreting viscera in, different feeble electric states, it is easy to conceive the production of acid and alkaline substances characterizing the secretions, and to understand the formation of new substances by the combination of the nascent elements. The electric state of the organ secreting particular fluids may also be deduced; and still further it might be expected, that alkaline secretions would contain substances in which hydrogen and carbon formed the principal part; whilst acid secretions would contain bodies abounding more in oxygen and azote. A brief consideration of the analysis of those substances which are found in the urine, milk, bile, saliva, &c., will shew generally the truth of this deduction

5. ON THE DISORDERS ARISING FROM THE LONG-CONTINUED USE OF IODINE.-(Dr. Jahn.)

The following is the account which Dr. Jahn gives of that diseased state of the system, which results from a long continued or excessive use of iodine, and which it will be found differs much, as do also the explanations of the effects, from the descriptions of MM. Coindet, Gardiner, Sceter, &c.

When introduced into the organic fluids, iodine acts firstly and principally upon the process of nutrition. The first evident effect is an absorption of the fat, so that a gradual leanness is remarked. At the same time, we may observe with a little attention, an augmentation of all the excretions. The skin, in consequence of an increased deposition of carbon upon it, appears dull and of a livid hue; there is great and clammy perspiration; respiration is obstructed, the urine is increased in quantity, and the surface of it is often covered with an oily pellicle. The alvine evacuations are increased, and the fæces are loaded with bilious matter and contain but little mucus; the seminal secretion is increased, and also the menstrual discharge. It is clear,' says M. Jahn, that in this state the vitality of the veins and lymphatic vessels is exalted, and the predominance of venous excitement is shewn, by the swollen state of the superficial veins, and the blue colour of the lips. The blood, it may be inferred from the diminished redness of the skin, and the feebleness of the arterial pulsations, has acquired a more serous character, and is more liquefied, so that the quantity of serum is greater in proportion to the cruor and fibrine. The energy of the irritable tissues is comparatively diminished. Hence the patient is more easily fatigued than before; digestion is

* Ann. de Chimie, xliii. 259.

irregular, the saliva and mucus are diminished, and complaint is made of dryness of the mouth and throat. The nervous power is also materially affected, and symptoms resembling hysteria and hypochondriasis arise, morbid sensibility, lowness of spirits, timidity, sensation of weakness, trembling of the limbs, similar to that produced by mercury, agitated sleep, with disagreeable dreams, &c.

At this period irregular and transient febrile attacks announce a reaction of the constitution. If now the morbid condition be not opposed, and if the iodine be continued, the above symptoms increase in severity, and shortly the glandular tissues, the breasts, testicles, and thyroid gland are diminished in substance. At length, all those symptoms arise, which are said to constitute nervous consumption.

M. Jahn has examined two bodies, which presented the traces of the action of iodine. A woman, who having misused the remedy, was attacked with enteritis, which proved fatal; and a man affected with cancer of the stomach, who was treated by the internal and external use of iodine, and who took very large doses of the tincture secretly, in hopes of a more speedy cure.

In the bodies of these patients the fat had disappeared, the various tissues had a withered and flabby appearance, the glands were shrunk and soft, and also the mesenteric ganglia (which are usually much developed in cancer of the stomach), the thyroid and supra-renal glands, the liver, spleen and ovaries.

Notwithstanding the mischief sometimes inflicted by the use of iodine, M. Jahn considers it one of the most valuable remedies which has been recently discovered*.

6. CHLORINE AN ANTIDOTE TO HYDROCYANIC ACID.

MM. Persoz and Nonat have verified the favourable results which M. Simeon had obtained relative to the remedy which chlorine affords against prussic acid. They operated upon three dogs, upon the eyes of which a drop of prussic acid had been placed. Dividing the symptoms into three periods, namely; i. uneasiness, ii. tetanus, iii. interrupted respiration they found that when chlorine was applied in the first period, the relief was immediate, the respiration became regular, vomitings and alvine discharges occurred, the animal gradually regained its strength, rose unsteadily, and, in about half an hour, was as lively as at first. Applied at the second period, the symptoms were arrested, but the restlessness continued awhile; and though respiration was less painful, the convulsive movements continued for ten minutes, then occurred vomitings, &c., as before, and, at the end of an hour, the animal was perfectly well. The two dogs thus treated being tried next day with the same quantity of prussic acid, but without chlorine, died in a few

minutes.

*Med. Jour., xlix., p. 72.

In the third case, all the effects of the prussic acid were produced before the chlorine was applied; the respiration had ceased for twenty-five seconds, and the animal was rapidly perishing; but the chlorine not only recalled it to life, but ultimately restored it to full vigour the full effect only occurred, however, after some hours. Ten days after it was quite well, and the paralysis of the abdominal parts, which occurred in all, had, in this case, entirely disappeared.

After this, MM. Persoz and Nonat sought to ascertain whether the prussic acid, being absorbed into the vessels and tissues, the chlorine would follow and decompose it. Two dogs of equal strength were taken, the crural veins laid bare, and separated from the neighbouring parts, and especially the accompanying nervous fibres; then a drop of prussic acid was put upon each vessel. The effects were instantaneous; a few drops of chlorine (solution) were let fall on to one of the crural veins-the other animal was left alone. The first was as immediately recovered as it was injured; the second died directly. The first felt no inconvenience after some hours, except from the wound. Endeavours were then made to kill him, by putting prussic acid upon the eye and upon the crural vein of the opposite side; but the animal only felt temporary inconvenience and a few convulsive movements, and was very quickly at ease. Hence it appears that the chlorine administered beforehand is taken into the circulation, and is then an effectual remedy against prussic acid.

Trials made with the chlorids of lime and soda, in place of chlorine, shewed that they possessed no corresponding powers, being quite inert as antagonists to the hydro-cyanic acid *.

7. ON THE CURE OF ANIMAL POISONS, AND PROBABLY HYDROPHOBIA, BY THE LOCAL APPLICATION OF COMMON SALT.(Rev. J. Fischer.)

The Rev. J. G. Fischer was formerly a missionary in South America, and is anxious to call the attention of the public to the probable utility of common salt, as a remedy in cases of hydrophobia, if at least the opinion be correct, that what will cure the bites of venomous serpents will be efficacious in the former class of cases. He says, I actually and effectually cured all kinds of very painful and dangerous serpents' bites, after they had been inflicted for many hours; for immediately after I had applied my remedy the pain subsided, and the patient calmed, which remedy was nothing else than common table salt; and I kept it on the place or wound, moistened with water, till all was healed, within several days, without ever any bad effect occurring afterwards. I, for my part, never had an opportunity to meet with a mad dog, or any person who was bitten by a mad dog; I cannot, therefore, speak from experience, as to

* Ann. de Chimie., xliii., 324.