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no 189 illegiusto cotton extremities? It appears to us that the heat generated by the quantity this very curious though very com- of carbonic acid produced, judging mon phenomenon is not very satis- of that quantity by the quantity factorily explained. It was at first given out in the conversion of carsupposed that the oxygen inhaled, bon into carbonic acid is sufficient combined with the carbon of the to preserve the temperature of the blood, and parted with the heat body, and that animal heat is which was latent in it, or kept it in caused chiefly by respiration; and, its gaseous state to the blood; that according to the process abovemenarterial blood contained more spe- tioned. The union of the carbon cific caloric, or latent heat, than of the body with the oxygen of the venous blood, which it gave out as atmosphere, is a slow combustion, it circulated through the body, and which, as it takes place, produces was gradually converted into the a constant supply of heat. If we latter. This theory, which was sug- believe, with Dr. Edwards, that the gested by Dr. Crawford, has been oxygen is absorbed by the blood, overthrown by its having been and gradually combines with its proved that there is not that differ- carbon, this theory seems to gain, ence between the specific caloric in probability. But it is inexplis of arterial and venous blood which cable if we suppose that the conDr. Crawford supposed; nor a version or combustion all takes sufficient difference between the place in the lungs. The objections, specific caloric of oxygen gas too, which have been made to this and carbonic acid gas to make theory, on account of the little difit possible for the former to part ference in specific calorie of venous with heat to the blood, and at the and arterial blood, and of carsame time preserve the fluidity of bonic acid and oxygen, do not apthe latter. But Mr. Brodie also pear to have much weight, when found, that when artificial respira we reflect that the body in general tion was kept up in the lungs of is never for any considerable time animals after their heads had been surrounded by media very differcut off, that carbonic acid gas was ent from its own temperature, and formed, and the circulation of the that consequently a small quantity blood kept up, and yet the animal of heat evolved by the circulation heat was rapidly diminished. Mr. of the blood is sufficient to preserve Brodie concluded, therefore, that animals at blood heat. It should the production of animal heat is also be remarked and remembered, owing to the action of the brain, that a quantity of heat sufficient to and not to respiration. A French- expand mercury to that point man, however, M. Le Gallois, has where water boils is destructive of since shown that the heat of ani life, and that consequently a very mals thus treated continued longer small quantity of heat, as judged than animals beheaded, and in the of by the expansion of the metal, heat in which artificial respiration can alone be requisite for the ani. was not kept up; and that animals mal economy. We do not say that became cold in proportion as the the matter is clear; on the con. combination of oxygen diminished. trary, it is not. We will, however, M. Despretz, whose memoir on go so far as to assert, that in the this subject we have already said present state of our knowledge, was lately crowned by the Acade. the probabilities are, that oxygen my of Sciences at Paris, made ex. gas is absorbed by the blood in the periments, first to demonstrate the lungs, and that as it circulates quantity of heat disengaged by the through the body, being gradually combustion of pure carbon, by converted into venous blood, there which it is converted into carbonic is also a gradual formation of card. acid gas; and secondly, the quantity bonic acid gas, or a slow combuske of carbonic acid gas formed by the tion which is the source of animal respiration of animals; and the heat. If this be at all a correct result of his experiments is, that view of the matter, then is the pro


daction of animal heat to be classed Now mercury having a greater with a great variety of other che- affinity for oxygen than silver bas, mical phenomena. If Mr. Bro- in the foregoing experiment the die's view of the question be cor- mercury deoxydizes the silver, rect, it is one of the phenomena which was before combined with which depend exclusively on the the oxygen of the pitric acid in principle of vitality, and will have which it was dissolved, to form to be explained according to some pitrate of silver, and the silver laws, the outlines or beginning of being thus deoxydized, is precipiwhich man has yet failed to dis- tated in its pristine metallic form. cover.ba

If zinc, iron, or any of the metals Lietu

having a greater affinity for oxygen 166113 THE SILVER TREE.. than mercury, were employed in1099010101

stead of that metal in the foretype To the Editor of the Chemist...

going experiment, it would, it da SIR,Many of the books on che seems, produce the same effect. If mistry which I have perused con- the nitrate of silver be not suffitaip very long and intricate ac, ciently diluted, the precipitated counts of the mode of producing metal, by its own specific gravity, the silver tree, or Arbor Dianæ, may fall to the bottom of the vessel equally tiresome and difficult to in which the experiment is made, understand and execute. But the instead of remaining suspended in following very short and simple it, which is the chief beauty of the method of producing it I have tried, experiment. and with success. "If there be any

Your constant reader, merit in the method it is not mine, July 26. Philo CHEMICUS. for I found it in a late publication, entitled Five Hundred Useful and Amusing Experiments, by George TO

TO MAKE OLD PORT WINE G. Carey, p. 17.

OUT OF NEW. » Pour a few drops of qaicksilver It is useful to be aware, that into à phial containing a solution port wine may speedily be renderof nitrate of silver, considerably ed aged by heat; and in this case diluted with distilled water. Leave it deposits its coat, and assymes the phial undisturbed for two or the marks of old wine to the eye, three hours, and the silver will be as well as to the palate. One year found precipitated in the form of will thus do as much for port as the branches of a tree.

five or six in the ordinary mode of ONB, I performed the experi- helping, but the period of its entire ment with a small open test-tube, daration will be comparatively and left it alone all night. In the shorter. The effects of heat in following morping the expected maturing port have hitherto been a result was beautifully perfect. secret in the hands of a few. In

Yogr younger readers may not America, it is a well-known prac. object to being informed that the tice to boil Madeira wine, or to rationale, or principle, of the fore- heat it to the boiling temperature, going experiment is as follows: and the effect is to impart to harsh As metals oannot be dissolved in new wine the qualities of that which àcids unless they are combined is ripe and perfect in flavour. This with oxygen, so they may be reco: practice is applicable to port. If vered from a state of solution, and newly-bottled wind be exposed to rovived, by deoxydizing them, that the sun, it shortly begins to depó. isoby depriving them of that pors' sit its colouring matter, and im. tion of oxygen with which they are proves in flavour; and even the combined when in solution, and rawest wine of this kind may, by this is effected by introducing ana heating it in hot water, be caused othed metal, or other substance, in the course of a day to assume which has a greater affinity for ox- the quality which it would have ygen than the metal in solution,' had after many years of keeping.

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It is so far from injurious, as might about. Previous to his letter reaching be imagined, that it is a valuable us, an article with a drawing describing secret, and, we believe, one that is the mode of prepuring nitric and mubatlittle known, even to those whose riatic acids had been got ready, and interest it is to give the complexion will appeur in No. XXIII. To receive of old wine to new, and who gene- the private information he requests, he rally effect this purpose in a frau- will see the necessity of sending some dulent manner, by putting it into more definite address. A letter to foul crusted bottles.- Encycl. Brit. Alpha, at Leeds,would be like the Supp. vol. vi.

sailor's, which he addressed," My Aunt

Bet, London." ; TO TAKE OUT FRUIT STAINS. Mr. Cobbett neither makes the plat To the Editor of the Chemist: himself, nor has he an agent in London,

Z. He intends, we understand, to take · SIR, -The last communication steps to have an establishment: To the

I sent you was not, I suppose, latter part of Z.'s recommendation we * worth keeping, so you lost it. If reply, that our principle is, Every inthis be so, I beg you will give dividual should buy what he wants yourself no trouble about it, as it wherever he can get it cheapest: best, will not trouble me. *

But if it be worth insertion in your weekly paper, (which I con- Cats-paw's second note in our next. stantly see) be it known to all. We shall be happy to hear the result of whom it may concern, that having his experiment...::. stained my white muslin dress with. fruit of different sorts, and being ' C. J. has been received. His third employed in pickling as well as note is more marvellous than the two preserving, some vinegar fell upon former. ... the stains, and which has had the effect of completely removing them. 2

We would readily have inserted thể

W. :If there be any novelty in the

letter of J. M., Rochester, but he la

to bours under a mistake. One of the application of vinegar for similar

books which he quotes, namely, Parke's pnrposes, it surely is an easy, simo ple, and indestructive remedy.

Cutechism, states the fact he alludes to

almost in the sumie words as were used Gio! Your humble servant, : ;

in The Chemist. According to a va. . A. D.'' luuble series of experiments of Count It would be convenient for ladies Sickenger, and by the experiments of who are your correspondents, if Mr. Rennie, the following appears to there were a letter-box, into which be the tenacity of the different metails they might put their communica- mentioned in the article on gold. Wire tions.

0.078 of an inch thick, when of iron, * supported a weight of 449.34lbs.; of

copper, 302.26lbs.; 'of platinum, TO CORRESPONDENTS.. 274.31lbs.; of silver, 187.13lbs.; and

of gold, 150.07lbs. If, therefore, a Alpha "will see we have done what mistake has been committed, it rests was in our power to procure him the with one of the eminent persons whose best information on the subject he asks assertions were quoted......... ..

** Communications (post paid) fo * Our fair Correspondent is quite mis-''; taken in supposing we lost her former

: be addressed to the Editor at the Pube

be addresser communication from entertaining a no- lishers'. tion that it was not worth keeping. In fact, we mislaid it from taking too great care of it, and have since found it: hereafter we shall publish it. Her suggestion London : Published by Knight and LA. at the end is already partly, complied • cey, 55, Paternoster-row. - Printed by with, but unfortunately the box is en B. Bensley, Bolt-court; Fleet-street. tirely within our publishers' shop.

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CONTENTS. Manufactory of Borax ...........: 338 To distil Spirit from Potatoes...... 349 Chemistry as a Science, Art. XXI. Effect of Air on Life.............. ib. "Arsenić. Antimony............ 339 To rectify and wash Ether ........ Analysis of Scientific Journals. An Method of preparing Oxygenated

nals of Philosophy for August. ... 341 Matches ..................... To prepare Citric Acid.......

To prepare Aloes Pills with Myrrh Gum makes Oil unite with Water.. To prepare pure Carbon ..... Dictionary of Chemistry .......

Query .............. Curious Experiments ............ ib. Answers to Queries .............. ** Manufacture of Sulphuric A

Chemical Society ............ * French Method ................

345 Natural History ................ Sulphuretted Hydrogen ......... 347

347 To purify Corn Spirit 1.000 Method of Plating on Copper...... 348


Curious Experlof

Sulphuric Aci

MANUFACTORY OF BORAX. considerable effervescence takes

This salt, which is of great use place, in consequence of the action in the arts, being employed as a of the boracic acid on the sub-carflux in soldering, and several ma- bonate of soda and the escape of the nufactures, was formerly brought carbonic acid. The liquid rises to to Europe from the East, and was some height, and care must, thererefined in Holland before it came fore, be taken to have coppers suffiinto the market. We believe it ciently large; they must be at least is not yet manufactured in our double the size necessary to concountry; and therefore the follow- tain the quantity of soda and boraing notice of the mode of doing it cic acid employed. The next poron the Continent is likely to be of tion of acid is not added tilt the some utility. Borax is a com-'effervescence has wholly subsided. pound of boracic acid, soda, and When the whole has been added, water; and the late discovery of and the effervescence has entirely free boracic acid, in considerable ceased, the fire is lessenedor quantities in lakes of hot mineral wa- damped, so as to keep the tempeters in Tuscany, has led to the esta- rature near the boiling point. The blishment on the Continent of ma copper is covered with a wooden nufactories for making borax. By lid lined with lead, and a woollen evaporating the water of these lakes covering is also putover it to keep in in graduating vessels, the acid is the heat. It is allowed to remain obtained at small expense. In in this state for 30 hours, and then consequence of this, borax is no · the clear liquid is drawn off, by longer imported into France; and means of a cock or syphon, into within a year several establishments vessels for crystallization. They have grown up in that country are of considerable dimensions; for manufacturing borax from the and the solution should not be boracic acid of Tuscany and the above 25 or 30 centimetres deep, in soda made in France. The borax. order that the cooling may be more thus manufactured has already rapid. At the end of three days in found its way into commerce. At winter, and four in summer, the first it was introduced as the re. crystallization is complete. The fined borax of Holland, and then mother water is drawn off and emsold for seven francs the kilo- ployed in the next operation, ingramme; in consequence, however, stead of water, to dissolve more of the success in manufacturing it, subcarbonate. Crystals of borax the price fell to 2 francs 60 cents. are deposited at the bottom and at which it is now sold. The sides, to which they adhere firmly, manufactory under the direction and must be removed cautiously. of the author of this Article, They are again dissolved in boiling which we take from the Dict. Tech- water, and 10 kilogrammes of subnologique, is capable, he says, of carbonate added to every 100 of making 50,000 kilogrammes, or the borax. This solution should be more than 100,000lbs. a year. The at 20% of the areometer of Beaumé, mode of proceeding is as follows:- and at least 1000 kilogrammes of Five hundred kilogrammes of wa- borax must be dissolved at the ter are boiled in a copper, in which same time to obtain large crystals, 600 kilogrammes of sub-carbonate they being in size always in proof soda are dissolved gradually, 20 portion to the mass. When the kilogrammes being added at a whole is again dissolved, it is time. The fire is covered with drawn while boiling into a vessel damp charcoal, and the mixture for crystallization. This should kept just boiling, so that as little have the form of a truncated vapour a's possible escapes, and pyramid, as represented in the 600 kilogrammes of the boracic plate, be constructed of consideracid of Tuscany is added, gradually able thickness, so as notuto be and successively, in portions of 10 easily shook, and be lined with kilogrammes. At each addition a lead. The lower base is a tect

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