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I found mouthfuls of a disagreeable water-like fluid rifing from my stomach, accompanied with diftreffing fenfations, and flight inclination to vomit.

I remarked that the fluid did not taste acid. Some chemical tests were at hand: I dipped the end of a flip of litmus paper into fome of the fluid, which fell on a board, and perceived no change in the colour of the paper.

I then dipped in the end of a flip of paper reddened by cæfalpinia, and found that it became fimilar in colour to the other end of the fame flip which had been dipped into alkali.

Concluding that an excess of alkali was prefent in my stomach, I took a little vinegar and water, and was presently relieved. I took a little more, and was quite well in one or two minutes. I am, Sir, with respect,

Savannah, August 8, 1804.

JOHN BRICKELL.

Dr. Victor Michelotti, has given in the Journal de Phyfique, Brumaire, year 12---a highly interefting paper, entitled, "Researches refpecting the action exercised by Caloric, on the vitality of animals." This experimental effay points out very clearly that animals are more injured by being slowly, rather than rapidly deprived of caloric. His experiments on caterpillars and fpiders appear to prove this. The Doctor thought it " of importance to ascertain what would take place during á continued privation of the caloric neceffary for the state of life," which, he fays, "might ferve to explain whether the real death of animals rendered torpid by cold, arifes from the want of that caloric necessary to the state of life, or rather from the manner in which they are deprived of it." Several interestview "to afcer

ing experiments are detailed, made with a tain what would take place, by rendering torpid and reviving alternately the animals, or by making them to pass slowly from heat to cold, and from cold to heat, or rapidly from heat to

cold." By thofe experiments (made on ants) he fays, "it is feen that if 9.9 in 100 died of those who were preserved in a state of torpor, on account of the cold continued for eight days, 88.2 in 100 die, of those who are fubjected to an alternate and flow privation of caloric, and that 25.5 in 100 die of those who have been fuddenly and alternately deprived of the caloric neceffary to the state of life."

"But it is ftill more remarkable," he elsewhere adds, "that if vital beings do not return to life but when they have been speedily deprived of the neceffary caloric, this law should be general, as animals expofed to exceffive heat, do not return to life but when their temperature is rapidly changed. As this may be eafily conceived, I shall mention only one example.

"Of four lively frogs, which appeared to be of the fame age, exposed in water to a heat equal to thirty-five degrees, [probably of Reaumur's fcale, 110.3 Fahr.] a degree fatal to these animals, only two, which were immerfed fuddenly at that temperature in water at fixteen degrees were recalled to life. It is always, therefore, a fudden privation of caloric which leaves organic beings in a state fufceptible of life."

The doctor fuppofes, in explanation of the phenomena he relates, "that the flow privation of caloric produces a greater debility, than rapid privation," and that animals are preserved in life by lofing in a speedier manner their caloric," becaufe the organic parts, by the help of a flow change, affume difpofitions which they could not acquire by a fudden privation."

By fome experiments of Fourcroy and Vauquelin, read before the National Institute, it appears that the bones of animals differ in compofition from thofe of men. This difference confists in the prefence of the phosphate of magnefia in the bones of all the animals they had examined, except in thofe of man. The method of feparating the magnesia from the bones of animals is pointed out, and its proportions in different animals.

These philofophers explain it, from a fact established by them on a former occasion, viz. " that the urine of men contains phosphate of magnefia, and that the urine of animals is free from it. This falt therefore is ejected in man, by the kidnies; it therefore does not enter into the compofition of his bones;" Nicholson's Journal.

"A new earth has been discovered by Profeffor Klaproth of Berlin, in an ore which was hitherto fuppofed to contain tungften, to which he has given the name of ochroit earth. "This earth feems to form the connecting link between the earths and metallic oxides," &c.

Ibid.

Suberic acid, mixt with oxalic acid is obtained by the action. of nitric acid upon paper, according to Brugnatelli.

Ibid.

Important and curious diftinguishing property between the galvanic and electric fluids, by Mr. Cuthbertson, in a letter to Dr. Pearfon, dated 27th March, 1804.

"1. Charcoal was deflagrated and ignited for above an inch in length.

"2. Iron wire, one-fortieth of an inch diameter, was melted into a ball one-fixteenth of an inch diameter.

"3. Platina wire, one-hundredth of an inch diameter, was melted into a ball one-tenth of an inch diameter.

"4. Brass wire, one-twentieth of an inch diameter, threefourths of an inch in length, was ignited.

"5. Brafs wire, one-fixteenth of an inch diameter, was red hot at the end.

"6. Iron wire, one-hundred-and-fiftieth of an inch diameter, was red hot for fixteen inches in length.

"7. Iron wire, twelve inches deflagrated, and melted into a ball.

“ 8. Iron wire, fix inches in length, was deflagrated.

"9. Iron wire, eight inches in length, was ignited.

"Two troughs, each trough containing thirty pairs of plates fix inches fquare, were used for the first seven experiments, and one of thofe troughs only for the two laft experiments.

"The four laft experiments, prove, I think, that double quantities of Galvanic fluid only burn double lengths of wire, and not the Square, as electrical difcharges do." Tilloch.

Two new metals are faid to have been difcovered in Crude Platina. A paper on this fubject by Smithson Tenant, Efq. F. R. S. was read at the Royal Society with an account of their properties. He has given the name of iridium to one, from the various colours of it in folution; and that of osmium to the other. Nicholson's Journal. Jofeph Hume, Efq. in a letter to Mr. Tilloch, fuppofes the iridium to be only tungsten.

To the Editor of the Philadelphia Medical Museum.
DEAR SIR,

ACCORDING to my promife, I fend you a receipt for making an indelible ink, fuperior to that imported from London, confiderable quantities of which, have lately been fold in Philadelphia.

I am, Sir, with respect,

Your humble fervant,

JAMES WOODHOUSE.

Diffolve four drachms of the nitrate of filver or lunar cauftic of the shops, in four ounce measures of rain or river water, and when the folution is clear, add to it fixty drops of an infufion of galls, made by pouring a gill of boiling water, on two drachms of powdered galls.

Diffolve one ounce of pearl-afh, in four ounce measures of water, and let it ftand until the folution becomes clear.

Dip a flat stick in the folution of pearl-ash, and impregnate the article in the part to be marked with it, and let it be well dried. Then write over it, with a clean pen, having a ftiff nib, dipped in the folution of lunar cauftic, holding the gallate of filver fufpended, and the letters will be formed of a black colour.

When an infufion of galls is added to a solution of the nitrate of filver, the gallic acid unites to a portion of the oxide of filver of the nitric folution, and forms gallate of silver, which remains for a short time fufpended in the solution, and makes the ink, which confifts of gallate and nitrate of filver, flow from the pen in an equable manner.

When the ink comes in contact with muflin, linen or cotton, impregnated with the folution of pearl-ash, a double elective attraction takes place. The gallic and nitric acids, unite with the pearl-afh and form gallate and nitrate of pearl-afh; the carbo nic acid of the pearl-afh joins the oxide of filver, and makes carbonate of filver, which is depofited upon the part written.

When articles, marked with this indelible ink, are washed, the gallate and nitrate of pot-afh, being foluble in water, are carried away, and the carbonate of filver remains behind.

When the gallate of filver has fallen to the bottom of the nitric folution, the veffel containing it, must be frequently shaken, to keep it fufpended.

The quantity of ink, mentioned in this receipt, will fill forty bottles, of the fize imported into this country.

The pot-afh contained in the vials brought from London, is coloured with cochineal or red faunders.

It is with pleasure we notice the formation of a new fociety by the medical characters of Savannah---under the title of the "Georgia Medical Society." It was organized in June---when 'the following officers were elected: Dr. N. W. Jones, prefident; Dr. J. Irvine, vice-prefident; Dr. L. Kollock, treafurer; Dr. J. Grimes, fecretary.

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