even when clean bills of health are issued. All these half measures, the useless quarantine upon the Barbary States, its partial removal from Turkey, its continuance upon Egypt when healthy, are the results of the timidity of the Academy in putting their scientific conclusions into practical application,-and we have still to urge our old propositions.

1. To furnish all ships with clean bills of health where no plague is present at the port of departure, and with foul bills in the opposite state. 2. To receive all ships with clean bills of health in free pratique.

3. To impose eight clear days after arrival and ventilation of cargo to all ships with a foul bill.

4. In case of any suspected disease on board, the quarantine to be regulated in duration by the local authorities.

These are plain and definite applications of science to practice, which afford security to the public and but little inconvenience to individuals, or impediment to commerce, and concentrate the attention of the sanitary guardians upon the real seat of danger. A far nobler work still remains to be accomplished-the annihilation of the scourge which has been so fatal to our race. The work is begun, and we earnestly hope that the Arab may have cause to bless our country for its completion.

P.S. Since the preceding article, which was intended for our April number, was written, we are happy to say that both the French and English governments have adopted the rational system of quarantine advocated in it and in our former articles on the subject. The boon thus conferred on commerce is immense, while it is gratifying to know that it is exclusively to the exertions of medical men that the important changes have been brought about. We give the French ordonnance, dated 18th April, in an abridged form; the shorter English document we print in full.

I. FRENCH REGULATIONS.

"1. Vessels arriving from impested places will in future only be distinguished by clean and foul bills of health, the latter only to be given when, in a place of departure or in places therewith in free communication, some pestilential epidemic exists under circumstances dangerous to the public health, and is to be given the day of or the day before the departure of the vessel. 2. Vessels from Turkey or Egypt, with an authorized sanitary officer on board, will be admitted on arrival with a clean bill of health to free pratique if the voyage have occupied ten days. 3. Those from Turkey without a sanitary officer to have a quarantine of three days in the Mediterranean ports and one day in other French ports. 4. Those from Syria and Egypt, with a clean bill, and without a sanitary officer, to five days. 5. Those with a foul bill to have ten full days from arrival. 6. Those with a clean bill from Tunis to be admitted in free pratique. 7. Merchandise with a clean bill to be admitted in free pratique after a voyage of ten days, and with foul bill, three days after arrival. 8. In cases of disease on board ship the local authorities to decide the period of quarantine. 9. French sanitary physicians will be established in the Levant to sign certificates at the port of departure."

II. ENGLISH REGULATIONS.

"Council Office, Whitehall, 18th May, 1847. "Sir, I am directed by the Lords of the Council to state to you for the information of the Commissioners of Customs, that their Lordships, taking into consideration the healthy state of the Levant (with reference to plague) for several years past, have come to the determination of abolishing for the present all quarantine upon vessels arriving from the Levant (Turkey, Egypt, and Syria

included), whatever may be the nature of their cargo, provided such vessels are furnished with clean bills of health, having been first visited by the quarantine or other proper officer of Customs, and that the crews and all persons on board have been free from any suspicion of infectious disease during the voyage. You will therefore move the Commissioners of Customs to give the necessary instructions for carrying the above regulation into effect. I am, sir, your obedient servant, "Charles Scovell, Esq.

(Signed) W. L. BATHURST.

"Custom House, London, 21st May, 1847. "The aforegoing copy of a letter from Mr. Bathurst (one of the Clerks of the Council in waiting) is transmitted to the collector and controller at for their information and government. By order of the Commissioners."

ART. XVIII.

Researches on the Chemistry of Food. By JUSTUS LIEBIG, M.D., Professor of Chemistry in the University of Giessen. Edited from the Manuscript of the Author, by WILLIAM GREGORY, M.D., Professor of Chemistry in the University of Edinburgh.-London, 1847. pp. 176. WHEN we inform our readers that the preface to this work bears date “Giessen, 1st June, 1847," we feel assured that we have said enough to convince the most unreasonable of them that anything like a review of it (in the sense which we trust we have taught them to understand the word) is utterly out of the question on the present occasion. We regret this circumstance the less, because many parts, we may say, the greater part, admit as yet of no discussion; the volume being almost entirely made up of accounts of processes and results which are stated to have been respectively carried on and obtained in the Giessen Laboratory during the past year. "The present little work," says its author, "contains the analytical details of my investigations on these subjects, [the nature of the organic acid diffused through the muscular system, and that of the other substances contained in that system] which, in accordance with the plan of the Animal Chemistry, could not be introduced into that work.” Hence any criticisms that these investigations may evoke at the hands of other chemists will, if necessary, be laid before our readers when the new edition of the Animal Chemistry is completed.

THE FIRST SECTION is devoted, for the most part, to the proteincontroversy that has been going on for the last eighteen months between Mulder and Liebig, and as the question must still in a great measure be considered sub judice, we will, with a passing expression of our regret that a scientific difference could not have been decided in a less hostile spirit, proceed to the remaining parts of the volume.

SECTION SECOND.-On the constituents of the juices of flesh. Our author commences by showing that although Berzelius announced forty years ago that the acid reaction of the juice of flesh depended on the presence of lactic acid, no sufficient proof had ever been given of the real characters by which the acid could be identified, until the present investigations were undertaken; he then alludes to Chevreul's discovery (in the year 1835) of kreatine, to Berzelius's want of success in obtaining it, and to the fact that Wöhler and Schlossberger were enabled to isolate it. These researches constituted the whole of our knowledge in

regard to lactic acid and kreatine as ingredients of flesh. As we wish to give an abstract of Liebig's results rather than of his processes, we shall not trouble ourselves or our readers with his improved means of obtaining kreatine. It is at best a complicated and not very easy process, and he himself confesses to " 'many fruitless attempts." With regard to the physiological relations of this substance, we may observe that it seems to vary considerably in different kinds of flesh. "Of all kinds, the flesh of fowl and that of the martin contain the most, then that of the horse, the fox, the roe-deer, the red-deer and hare, the ox, pig, calf, and finally, that of fishes." (p. 45.)

The amount is greater in wild than in tame animals. The flesh of a fox fed on flesh for two hundred days did not yield so much as the tenth part of the quantity of kreatine obtained from foxes killed in the chase.

"The amount of kreatine in the muscles of an animal stands in an obvious relation to that of fat, or to the causes which determine the deposition of fat. From fat flesh there are often obtained mere traces of kreatine, and always much less than from lean flesh, for the same amount of muscular fibre." (p. 45.)

The following table gives the relative amount of kreatine in the animals specified :

1000 parts of the flesh of fowl yielded 3-05 kreatine.

Liebig has not been able to detect it in the substance of the brain, of the liver, or of the kidneys; but it is present in abundance in the heart of the ox, so that this organ is especially adapted for its preparation. He describes crystals of pure kreatine as "colourless, perfectly transparent, and of the highest lustre; they belong to the klinorhombic system, and form groups the character of which is exactly similar to that of sugar of lead. At 212° the crystals become dull and opaque, with loss of water." From four experiments it appeared that the water of crystallization expelled at this temperature averaged 12:17 per cent.

From several analyses it appears that the formula for crystallized kreatine is CN3H1106, and its atomic weight 149; while anhydrous kreatine has for its formula CN,H,O,, and for its atomic weight 131.

"If we compare the formula of kreatine with that of glycocoll (sugar of gelatine), it appears that crystallized kreatine contains the elements of 2 equiv. glycocoll (C.N2H,O6) + Í equiv. ammonia (NH). Kreatine dissolves easily in boiling water, and a solution saturated at 212° forms, on cooling, a mass of small brilliant needles. From a diluted solution it crystallizes very slowly, in somewhat larger crystals, often from two to three lines in length, and one line in thickness, which increase in size for twenty-four hours after cooling, if left in the liquid. 1000 parts of water at 64.4° dissolves 13:44 parts of kreatine, or I part of kreatine dissolves in 744 parts of water.

"In cold alcohol kreatine is nearly insoluble, 1 part requiring 9410 parts of alcohol for solution. In weaker spirits of wine it is rather more soluble.

"The cold aqueous solution of kreatine possesses, from the small quantity of dissolved matter, a weak, bitter taste, followed by a somewhat acrid sensation in the throat. When the aqueous solution of kreatine contains a trace of foreign organic matter, it decomposes very readily.......

"No quantity, however large, of kreatine can destroy the acid reaction even of the weakest acids, and it possesses no basic characters. It dissolves easily with the aid of heat in barytic water, and crystallizes from it unchanged...... But when boiled with barytic water, kreatine is decomposed, ammonia is disen

gaged, the liquid becomes turbid, even when the air is entirely excluded, and there is deposited carbonate of baryta in crystalline grains, the quantity of which progressively increases as the boiling is continued..

The action of strong mineral acids is very remarkable. A solution of kreatine, to which, while cold, hydrochloric acid is added, gives by spontaneous evaporation crystals of unchanged kreatine. But when heated with strong hydrochloric acid, a solution of kreatine no longer yields crystals of that substance. The same result is obtained with sulphuric, phosphoric, and nitric acids. When kreatine is dissolved in one of these acids, and the solution gently evaporated, crystals are obtained, which are very soluble in alcohol, a property not belonging to kreatine. These crystals contain a portion of the acid employed, in a state of combination.

"There is formed in this reaction from kreatine, by a transformation of its elements, caused by contact with strong mineral acids, a new body of totally different properties, a true organic alkali, which I shall call kreatinine." (pp. 51-3.)

Kreatinine, its preparation, properties, &c. Kreatinine may be obtained in a state of purity from its hydrochlorate or sulphate. The crystals belong to the monoklinometric system, and their measurements have been determined by Kopp. Kreatinine is much more soluble in cold water than kreatine, one part dissolving in 11.5 parts of water at 60°; and in hot water it is much more soluble. It communicates an alkaline reaction to its solution. It dissolves in boiling alcohol, and crystallizes on cooling. 1000 parts of alcohol at 60° dissolve 9.8 parts of kreatinine.

By various reactions it is shown to be a powerful base; in fact, Liebig observes that, "in its chemical character, kreatinine is quite analogous to ammonia."

The conversion of kreatine into kreatinine is shown to depend on the separation of 4 eqs. of water.

Kreatine (CN,H,,06) Kreatinine (C,N,H,O,) + 4 HO.

8 3

=

8

"If we compare with the formula for kreatinine that of caffeine (théine), it appears that kreatinine contains the elements of 1 atom of caffeine + 1 atom amide.

1 at. amide
NH2
The sum is C ̧N,H,O2

We now pass from the consideration of the fluid of muscular flesh to that of the urinary secretion. Those of our readers who are conversant with the chemistry of the secretions, must recollect that about three years since a new nitrogenous substance was discovered almost simultaneously in it by Pettenkofer and Heintz. This substance contains the same proportions of carbon and nitrogen as kreatine and kreatinine; in fact, Liebig shows that it is nothing more than a mixture of kreatinine with a little kreatine, which may be easily separated from one another by means of alcohol; one of them (as we have already stated) being easily soluble, the other very sparingly soluble in hot alcohol.

The composition of these two substances, as obtained from urine, was found to be as follows:

"If we compare these numbers with those obtained by the analysis of kreatine from flesh and the analysis of the kreatinine prepared from it, it is obvious that they are respectively identical, and indeed no difference can be detected in the physical and chemical characters of the two substances from urine and those from flesh." (p. 64.)

During the putrefaction of urine, the kreatine is destroyed by the action of the carbonate of ammonia formed from the urea, while the kreatinine suffers no change.

Liebig regards the urine as not only the most economical but also the most convenient source of these compounds.

In a subsequent portion of the work it is shown that kreatinine is an actual constituent of muscle, or, in other words, that it exists ready formed in flesh, and a simple process for extracting it is given.

We now arrive at the consideration of a new substance, Sarcosine, obtained by the action of boiling barytic water on kreatine.

Sarcosine crystallizes in right rhombic prisms, acuminated on the ends by surfaces set perpendicular on the obtuser angles of the prism. The crystals are colourless, perfectly transparent, and of considerable size. They are extremely soluble in water, very sparingly soluble in alcohol, and insoluble in ether.

The aqueous solution of sarcosine has no action on vegetable colours, but from the mode in which it combines with acids it evidently acts as a powerful base. Liebig deduces for it the formula CN,H,O,, which serves to explain its production from kreatine.

7

"If from the elements of crystallized kreatine we subtract those of sarcosine, there remains a formula exactly identical with that of urea :

"It is consequently obvious that, in the decomposition of kreatine by baryta, carbonic acid and ammonia are secondary products derived from the decomposition of urea." (p. 75.)

In further confirmation of this view, Liebig has not only ascertained that a solution of urea in barytic water is resolved by long boiling into carbonate of baryta and ammonia, with the same appearances as those occurring in the production of sarcosine, but further, that urea is present in the liquid when kreatine is boiled with baryta, if examined before the whole of the kreatine is decomposed.

Sarcosine and urea are not the only products of the decomposition of kreatine by baryta; another substance of a feeble acid reaction, but not combined with baryta, was observed; it crystallized in long colourless prisms or scales, very soluble in water and alcohol. The quantity was too small to admit of an ultimate analysis.

Inosinic acid. When the liquid from flesh has entirely deposited the crystals of kreatine, and is somewhat further concentrated by evaporation, if alcohol be added to it in small quantities till the whole becomes milky, it deposits in the course of a few days yellowish or white crystals of salts of inosinic acid. The solution of inosinic acid has "a strong acid reaction, and possesses an agreeable taste of the juice of meat." When evaporated, it yields a syrup which after weeks exhibits no signs of crystallization. If