j-ji OUaginoiis Metallic Compounds. — On the Rachitis. 



but though by this means it attacks them all, it neverthclefs diflblves much lefs than the oils, 



particularly the oil of turpentine. 



I calcined part of the combinations here ilefcribed to determine the quantity of earth or 

 metallic calx tfiey contained. I employed half an ounce of each. The refidue of magnefia 

 -amounted to 32 grains, which did not effervefce with an acid ; that of calcareous earth 

 was 36 grains, which efFcrvcfccd ; that of clay 28 grains; of iron 4K grains; of copper 33; of 

 2ine 42; of mangancfc 40 ; the refidue of lilver amounted to 30 grains in the metallic ftatc; 

 that of tin 1 gros 7 grains of the reduced metal ; tliat of lead formed by calcination a pyropho- 

 rus. When thefe combinations are to be made, it is proper to ull- the folutions in a faturated 

 ilate; for, if there bean excefs of acid,part of the fcap is decompofed by tliiscxcefs ; a portion 

 of the oil floats above ; but part of the oil enters the combination which is formed, and alters 

 its properties. In whatever acid an earth or a metal may be dilTolved, the fame com- 

 bination is always formed by means of foap ; neverthelefs this combination fometimes ex- 

 hibits different appearances. Thus the oily compound of mercury is much more tenacious 

 arid adhefive when corrofive fublimate is ufcd, than when the nitrous folution of the metal 

 has been employed *. 



When the filtered liquor, after forming the oily combination, is evaporated, a fait is ob- 

 tained of the particular kind which refults from the alkali of the foap, and the acid of the 

 folution made ufe of. M. CoRel made the experiment with felenite, and I repeated it 

 with Epfom fait and vitriol. I firfl evaporated to perfetl drynefs, after which I dilTolved 

 the refidue in filtered water, and then evaporated and cryftallized f. 



Analyfis of a Memoir of Citizen BoNHOMME on the Nature and Treatment of Rachitis, or the 



Rickets %. 



OINCE the objeft of the Society of Medicine, in the offer of its prizes, is to bring our 

 knowledge of the healing art to the greateft degree of precifion and accuracy of which it 

 is fufceptiblc, this company mufl neceffarily direil its attention to the progrefs of the che- 

 mical analyfis of animal matters, and the information which fooner or later it mufl; afford 

 refpecling the nature and treatment of many difordcrs. 



Thofc diforders which alter the compofition of the fluids and the confillence of the folidi, 

 are affuredly the firft which ought to be determined by chemical refearch. '1 he rachitis 

 is of this number. The change which the bones undergo in this diforder, has long been 

 attributed to the adlion of an acid on their fubftance ; but this opinion was grounded on 

 mere fuppofition and remote analogy. The fubjefl is treated in a new manner in the me- 

 moir, of which the Society has dircded us to prefent the refults ; and the experiments as 



• Subfcqucnt experiments have flicwn that a much greater quantity of oxigenc is prefent in the former than 

 in the latter cafe. N. 



+ I fuppofe M. Berthollet's experiments were made with foap of vegetable exprcflcd oil. The common 

 ibapi of this country contain animal fat. N. 



t This Memoir was read to the National Society of Medicine at Paris. The analyfis was made by Halle, 

 2iul is infcrted in the feventceiuh volume of the Annales dc Chimie, whence this tranflation is made. 



weU 



