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the same quantity as her fellow. On her arrival in Glasgow her milk greatly increased, but it soon began to diminish, although the same amount of food was continued. That the change was not produced by any alteration in the food is obvious from the steadier result afforded by the white cow, which was also supplied with an equal weight of fodder. The amount of milk given by the brown cow was as much as 26 lbs. per day when she was fed with grass, and upon the same kind of food the quantity declined to 22 lbs.; while the milk produced by the white cow was, at the commencement of the experiment with grass, 23 lbs.; and at the termination of the trial, 21 lbs. ; so that there was a falling off, in the case of the brown cow, to the extent of 4 lbs., and with the white cow only to the amount of 2 lbs. That this result was not merely owing to a deficiency of water was proved by experiment, which gave the same amount of water in the milk of both cows; but the quantity of butter afforded by the brown cow amounted to 114 lbs., while that of the white cow was 3 lbs., in fourteen days, from 1,427 lbs of grass supplied to each animal. Again, when the animals were fed on steeped, entire barley, the brown cow's milk fell from 22 lbs. to 17 lbs., while that of the white cow's only declined from 22 lbs. to 19 lbs.; the brown cow falling off to the extent of 5 lbs., and the white cow only to the extent of 2 lbs. These facts are sufficient to show that the two animals were con

stitutionally different. The occasional wild look of the brown cow, her tendency to gore those who approached her, her frequent startled aspect, all indicated a nervous state of excitement; the probable cause of which has been already alluded to. The result of these experiments seem to countenance the idea that, although a handsome external figure is not necessarily an indication of the highest capacity in a cow to produce milk and butter, yet that it may conduce to afford a steady supply of milk, inasmuch as it appears to indicate a proper relation between the organs.

The first set of experiments were conducted to ascertain the influence of grass in the production of milk and butter; the animals were fed on rye grass (lolium perenne,) and it was found that 100 lbs. of dry grass produced 11.6 lbs. of dry milk, 33'6 of dung, and 2.71 lbs. of butter.

From these experiments it therefore appears that the same quantity of food given to cows nearly of the same weight, produced 5lbs. less of solid matter of milk in one cow than the other; 100 lbs of solid matter of grass producing in the brown cow 17 lbs. of dry milk, and in the white cow only 15 lbs. It appears, however, that both cows were in

creasing in weight; but, as the white cow advanced most rapidly, it is probable that the difference in the quantity of solid milk may have been applied to increase the weight of the white cow. There is another alternative which is also admissible-viz., that the capacity of the lungs and respiratory organs of the white cow were greater than those of the brown cow, since the former absorbed a greater amount of solid matter from the grass, as appears from the difference between the grass and dung, than in the case of the brown cow. These important differences in the two animals rendered it impracticable to make comparative experiments upon them at the same time. The only method which could afford results of value was to supply each with the same kind of food," and thus to obtain data which could enable a judgment to be formed as to the relative nature of the constitutions of the animals.

The succeeding experiments consequently were parallel and not comparative sets with the two animals.

While these experiments were being carried on by Dr. R. D. Thomson, other matters more relatively connected with the subject were not forgotten. The constituents of the food which supplies the butter for instance, were examined into. On this point he says:

It is now upwards of a century since Beccaria of Bologna broached the idea that animals are composed of the same substances which they employ as food: "En effet, si l'on excepte la partie spirituelle et immortelle de notre étre, et si nous ne considerons que le corps, sommes nous composès d'autres substances que de celles qui nous servent de nourriture?" (1742.) Collection Academique, tome x. p. 1. In more recent times Dr. Prout has defended the same doctrine, and has referred us to milk as the type of nourishment. In this fluid the main solid constituents are oil, fibrin, and sugar; these, therefore, or analagous bodies he considers should enter into the composition of all wholesome nutriment. Still more lately a difference of opinion has resulted with reference to the exact part which starch or sugar plays in the animal economy. brinous matters, it is generally admitted, undergo little or no alteration in the system; but whether it is necessary, in order to produce fat in an animal, that the food should contain oil, and that no other form of nutriment can produce this substance, is a question which has been very much debated. A French chemist, Boussingault, contends that the presence of oil, if not essential in the food, is at least very important in increasing the amount of fat deposited; while Liebig holds,

Fi

that oil may possibly be assimilated or converted into butter, but that the same product may result from the deoxidation of starch or sugar in the animal economy. To the agriculturist, the settlement of this question is of no small importance, since it may guide him in the use of various kinds of food for the fattening of cattle, which may otherwise be overlooked, and may also conduce to the proper preparation of food-a subject which has received less attention than perhaps it deserves. In the prosecution of the present series of experiments, the prospect of throwing some light upon this interesting subject has been kept in view, and, in general, such experiments as were required to afford data for calculating from different kinds of food, the probable origin of the oily matter secreted by the animals have been carefully registered. To solve the question, it is necessary to ascertain the amount of oil in the food. The oily matter in the grass was determined by first drying the grass at a temperature of 212°, to remove water: it was then digested in successive portions of ether, until that liquid ceased to remove any matter in solution. The same experiment was performed with the dung. The first process, therefore, gave all the oily matter swallowed by the animal, and the second afforded the oil or wax which was not taken into the system; 2000 grains of grass when dried became 500 grains. By digestion in ether 42-3 grains were taken up of a matter having a dry waxy consistence, possessing a green colour, but without any of the characters of a fluid oil; this is equal to 2.01 per cent. 4,284 grains of moist dung from grass, equivalent to 500 grains of dry dung, afforded 13.2 grains of an exactly similar green waxy matter to that found in the grass, equal to 0.312 per cent. The largest amount of wax in the dung of the cattle was obtained while they were feeding on hay; 1,000 grains of dung left, at the temperature of 212°, 157 grains of dry dung, which gave 6 grains of wax, equivalent to 0.6 per cent. in moist dung, or 3.82 per cent. in the dry dung. All these products were carefully dried for some days at the temperature of boiling water. From these data, then, we are enabled to construct the following table :

Amount of oil and wax in food of both cows in fourteen days.. Amount of oil or wax in dung ..

57.3 lbs. 6.3

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To ascertain whether the whole of the butter is removed from the milk by the usual process of churning, portions of the same milk were analysed by the usual methods for the sake of comparison. The brown cow's milk in the present experiment contained 346 per cent. of butter, while, by analysis, the amount was 3.7, making a difference of rather less than a quarter of a pound in 100 pounds of milk. This is so small that it does not effect the preceding calculation, but rather tends to show that the determination of such questions on a large scale is preferable to the usual analytic methods, since the analysis of milk twice a day for several months would be such a laorrious work as to render its accomplishment impossible.

It is necessary to explain the circumstance that butter, as obtained by the usual mechanical process, contains foreign matter, consisting of water and curd or casein. By analysis, butter was found to have the following composition :

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The composition of French butter has been stated to be somewhat different, as it has been found to contain upwards of eighteen per cent. of impurity. This may be owing to the coldness of the summer during which the present experiments were made.

The hardness of the butter was a subject of general remark, and might render it better fitted for being freed from casein than if it had possessed a more fluid form.

The cause of tainting of fresh butter depends upon the presence of the small quantity of acid and water as exhibited by the preceding analysis. To render butter capable of being kept for any length of time in a fresh condition, that is, as a pure solid oil, all that is necessary is to boil it in a pan tili the water is removed, which is marked by the cessation of violent ebullition; by allowing the liquid oil to stand for a little while the curd subsides, and the oil may then be poured off, or it may be strained through calico cr muslin, into a bottle, and corked up. When it is to be used it may be gently heated and poured out of the bottle, or cut out by means of a knife or cheese gouge. This is the usual method of preserving butter in India (ghee) and also on the Continent, and it is rather remarkable that it is not in general use in this country. Bottled butter will thus keep for any length of time, and is the best form of this substance to use for sauces.

From the preceding table it appears that the oil consumed by the cows greatly exceeded the butter, and the oil contained in

the dung, even if the casein and the water were not subtracted from the butter; the total quantity of butter being 191bs. 6oz. The result of this experiment is in perfect accordance with the facts observed by Boussingault, who, in similar researches upon cattle, found the oil in the food to exceed that in the dung and milk. The matter extracted by ether from grass, however, can scarcely be termed an oil, since it possesses all the characters of a wax; that is, a body which contains a smaller amount of oxygen than the fat oil certainly less than is contained in butter. It is therefore difficult to conceive a wax to obtain more oxygen in the system and to be converted into an oil, where all the actions are calculated to remove oxygen, and not to supply it; such an occurrence would be as probable as the addition of oxygen to wood by throwing it into the furnace. The production of butter from sugar by the action of casein or curd is, on the contrary, a process with which chemists are now familiar, and is therefore more readily admissible into physiological theories than the idea of the formation of butter from wax, since we are unacquainted with any analogous example. The connexion between sugar, oil, and wax is exhibited by the following formula. Carb. Hyd. Oxyg. Sugar 48 44 44

Differences. Carb. Hyd. Ozgy. Fat 44 40 4 4. 4 40 Wax 40 40 2 4 0 2 In bees we have a well demonstrated example of the production of wax from sugar, while fat, or the intermediate stage, is probably first produced in the body of the bee, and is then, by the loss of a small portion of carbon and oxygen, converted into wax, cr to the lowest state of oxidation existing in the animal system. The point, therefore, to which it is necessary to direct attention is, that we have instances in chemical physiology of substances being produced from the others preceding it in the table, but that we are unacquainted with any phenomena of an

inverse order; nor would such an occurrence be explicable upon the principles on which the animal system is understood to proceed. Taking all these circumstances into consideration, it appears that there are fewer difficulties in the way of supposing that butter is formed from the starch and sugar of the food, than from the waxy matter which is present in such considerable quantities. There is only one instance, with which physiologists are at present acquainted, that could be adduced as evidence in favour of any substance being rendered more complex in the animal system, viz., the production of fibrin or flesh from curd or casein. So far as chemical experiments carry us we are not in a condition to affirm that no fibrin exists in milk, but it is admitted that none has as yet been detected. If these be correct, then it would appear to follow that the infant fed on milk must derive its flesh from the curd of that fluid, and that as curd contains no phosphorus (while fibrin does) the curd of the milk, in order to form muscular fibre, is united to phosphorus in the animal system, and is thus built up, instead of being, as is the rule with other substances, reduced to a smaller number of elements. The composition of the two substances is as follows:

Casein or Curd. Carbon. Hyd. Oxygen. Nitro. Sulph. Phos. 54.96 7.15 21.73 15.80 0.36

Animal Fibrin.

54.56 6.90 22.13 15.72 0.33 0.36

The objection to this view of the subject is that the experiments which have been made on fibrin do not prove that it contains phosphorus ; they only prove that phophoric acid can be detected in it, even when it is purified in the most careful manner suggested by chemical knowledge; and it would therefore the somewhat premature to adopt any such analogy as that which we have been considering.

(To be continued.)

325

III. PHARMACY, MATERIA MEDICA, THERAPEUTICS,

&c.

THE ACTION OF HYDROCYANIC | blood; but that it can only act through the

ACID AS A POISON.*

BY DR. MEYER.

THE Doctor states as the result of his experiments with this acid on animals-

"1. That it had a paralyzing action on the peripheric nerves-i. e. it suppressed sensation and motion, and occasioned congestion, with augmented secretion, which was chiefly observed in the cavity of the mouth. 2. He found it to act only when received into the vascular system. On mechanically arresting the circulation, the poison did not act, although the integrity of the nervous system was preserved. On restoring the circulation, the operation of the poison was immediately observed. 3. Hydrocyanic acid does not act so rapidly as it was formerly believed. Its operation was never instantaneous. 4. Its fatal effect is owing to paralysis of the heart induced by the topical action of the blood, mixed with hydrocyanic acid, upon that organ. It required about thirty seconds for the poisoned blood to reach the heart and produce its paralysing effects, and it mattered not whether the poison was applied directly to the substance of the heart, or to parts remote from it. In Dr. Meyer's opinion, prussic acid may act independently of the brain or nerves, or of their intervention. It requires for its operation, absorption and diffusion until it reaches the heart. It is owing to this, in his opinion, that amphibia are less rapidly killed by this poison than mammalia, the action of the heart in those animals being less necessary for the maintenance of lite. Nevertheless, in a certain dose the poison may act upon and paralyze the nervous system, producing tetanic convulsions, congestion of the veins, and exudations in the serous cavities. It is not true, as it is generally believed, that in death from prussic acid the blood does not coagulate. Dr. Meyer found that this liquid coagulated in the bodies of the animals which were killed in his experiments."--British and Foreign Review.

These observations are to a certain extent confirmed by an experiment of Liebig. He endeavours to prove that prussic acid does not act by sympathy through the nervous system, nor is it absorbed directly into the

* Lancet.

medium of its vapour on the pulmonary mucous membrane. If this statement be correct, it may be made to act as a poison, and yet with difficulty be discovered after death.

NOVEL APPLICATION OF HYDROCHLORATE OF MORPHINE.*

BY M. EHRARD.

IT is well known that all kinds of neuralgia, and more particularly odontalgia, are very difficult of cure, although they may be considerably modified by means of preparations of opium, and particularly hydrochlorate of morphine. M. Ebrard believes, that if this last substance is not more efficacious, it is because it is not properly administered.

In fact, hydrochlorate of morphine, according to M. Ehrard, should be applied to the gums by friction on the affected side. M. Ehrard asserts that this simple change in the mode of application will, in a short time, remove the most afflicting toothache.

The author makes several observations which appear to be decisive. It is particularly in the case of those who are feeble, delicate, and extremely nervous that this mode of treatment is successful, and in many cases the pain arising from carious teeth has disappeared as if by enchantment.

The following is the mode of proceeding adopted by M. Ehrard :

The first day the patient takes 13 milligrammes of the medicament on one of his fingers, previously wetted, and he rubs the affected gum with it for the space of three minutes, he then holds his head on one side, taking care neither to spit nor swallow, to give time for the absorption of the salt; and afterwards he swallows his saliva.

At the end of two hours the operation is to be repeated.

On the following day, if the disease continues, we increase the dose, if necessary, to 37 milligrammes.

In frontal neuralgia, M. Ehrard employed hydrochlorate of morphine with the most marked success, by applying it to the mucous lining of the nostrils.

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THE ISLAND OF CHUSAN, CHINA.
ON THE EFFECTS OF THE CLI-
MATE ON EUROPEAN CONSTI-
TUTIONS.*

tities of blue pill every day. I preferred fasting, and believe I cured myself by that means; but I could persuade few to adopt this remedy; they preferred eating, drinking, smoking, and blue pill. I have heard no one assign any probable cause for this disease; some attribute it to bad air, and some to bad water; some thought that the Chinese had poisoned the springs, but we found no change when we drank Thames or Indian water from the ships, and we saw nothing that could produce malaria. There was ro sea-beach, swamp, or uncultivated land. The coast was hills and rocks. The rice-grounds were few and small, and no change was observed, either when they were covered with water or drained. I have attributed this disease to a certain electric state of the locality. The following will be my reason for doing so :

The coast of China is the eastern coast of the largest tract of land in the world—of the great eastern continent, extending in longitude from the east of China to the west of Africa. It is also bounded by the largest tract of water-the great Pacific Ocean.

BY FRANCIS DELAVAL WALSH, ESQ. HAVING resided some time on the coast of China, I forward these few remarks on a peculiar disease that prevails there, and afflicts nearly all Europeans that newly arrive; I may safely say, that out of a thousand that went down the coast as far as Chusan during the late war, not one escaped. I mention this as the average. Those who had been there previously, promised us that we should all certainly be sick as soon as we set foot on the coast of China, though we had never been sick before. It happened so; I was sick there for the first time since I had been out; so were all that were with me, soldiers and sailors. No sooner were we anchored in Chusan harbour, than we were seized with pains in the bowels, and loss of appetite. Some vomited, and all had diarrhoea; nothing that we ate agreed with us, though we tried all sorts of food. The soldiers on shore were Now, there is a current of electricity nearly all in hospital; in one company there passing round the world from west to east, were only two men able to do duty. The (see Faraday); and electricity is conducted same disease attacked all the officers. It better by water than by land. Electricity, was a common occurrence to see thirty or then, will be positive on the western, and forty officers sit down to dinner, and then negative on the castern coast; or on the one jump up and run out as soon as they had it will be plus, and on the other minus. swallowed the first spoonful of soup; so that Now we have pretty good proof, that where they used to call the disease the Chusan trot. electricity is négative, vitality is depressed; It was called the main-deck trot by the where it is positive, it is excited. The hand sailors. Some soon recovered, but were very placed in the negative current, becomes cold, apt to relapse upon the least change of in the positive, warm ; and many practitioners weather, as, for instance, a shower of rain. in India have remarked, that there are pecuDr. P. Grant, who inspected the hospital at liar diseases in connection with peculiar Chusan, said it was the most troublesome electric states of any locality; that there is a disease he ever had to deal with. The men remarkable difference in the biliary secretion; kept leaving the hospital, and returning the liver is excited where the electricity is again, at every relapse losing flesh, and be- positive, depressed where it is negative. Now, coming weaker, until they were quite worn in diseases on the coast of Africa, the pracout, and many died. titioners complain of excess in the secretion of bile; on the coast of China, of deficiency. In the diseases of China, there was a complaint that no bile was secreted. This is directly the reverse of the diseases on the coast of Africa: an excess of the action of the liver is complained of in the same latitude with the same heat of climate. Bleeding is more resorted to on the coast of Africa, and calomel in large doses, to act as a sedative. In China, bleeding was seldom resorted to with good effects; and calomel was found beneficial in small doses, to act as an excitant. From these reflections, I question if the coast of China will ever be a healthy place, either for Europeans or for natives of India: both seem equally to suffer from disease.

This disease, though troublesome and fatal, could be easily relieved. Anything that excited a secretion of bile gave temporary relief. It seemed that the liver had refused to secrete bile, or act, and yet did not become inflamed or congested, but torpid or inactive. The circulation through the portal vein was diminished; the intestines were congested; the stools liquid, frothy, and clay-coloured, something like brewer's yeast in appearancesometimes mixed with undigested food lately taken. If by means of calomel or blue pill we could excite the secretion of bile, the disease was relieved for a time. Some were so conscious of this, that they took small quan

* Lancet.

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