100 
POISONS : THEIR EFFECTS AND DETECTION. [§ 7 I. 
toxicology, and the quinine method for this purpose meets every conceiv¬ 
able case, both for qualitative and quantitative purposes. 
Free sulphuric acid in the stomach or intestines will probably not 
be found unless death is rapid. Bischoft’, 1 in the case of a woman dying 
in six hours from sulphuric acid, and the autopsy having been made 
sixteen days after death, found 12-5 grms. of free sulphuric acid from the 
stomach and intestine, and 2*8 grms. from the neighbouring organs. 
From the liver he obtained per 100 grms. of tissue 0'33 grm., kidney 
0*65 grm., free and combined acid; he gives the normal content of S0 3 
of these organs as : liver -0052, kidney -045, and spleen 0 per cent. 
There have been many similar cases, but so often has the free acid not 
been found that Buchner declared that the “ chemical detection of a 
poisoning by nitric or sulphuric acid is as a rule impossible ” ; this 
statement is too absolute, and contradicted by experience. 
§ 71. The Urine. —Although an excess of sulphates is found constantly 
in the urine of persons who have taken large doses of sulphuric acid, the 
latter has never been found in that liquid in a free state, so that it will 
be useless to search for free acid. It is, therefore, only necessary to add 
HC1, to filter the fluid, and precipitate direct with an excess of chloride 
of barium. It is better to operate in this manner than to burn the urine 
to an ash, for in the latter case part of the sulphates, in the presence of 
phosphates, are decomposed, and, on the other hand, any organic sulphur 
combinations are liable to be estimated as sulphates. 
It may also be well to pass chlorine gas through the same urine which 
has been treated with chloride of barium, and from which the sulphate 
has been filtered off. The result of this treatment will be a second 
precipitate of sulphate derived from sulphur, in a different form of 
combination than that of sulphate. 
The greatest amount of sulphuric acid as mineral and organic 
sulphate is separated, according to Mannkopf 2 and Schultzen, 3 within 
five hours after taking sulphuric acid ; after three days the secretion, 
so far as total sulphates are concerned, is normal. 
The normal amount of sulphuric acid excreted daily, according to 
Thudichum, is from 1*5 to 2-5 grms., and organic sulphur up to -2 grm. 
in the twenty-four hours, but very much more has been excreted by 
healthy persons. 
Lehmann made some observations on himself, and found that, on an 
animal diet, he excreted no less than 10*399 grms. of sulphuric acid 
per day, and on mixed food a little over 7 grms. ; as Thudichum 
justly observes, this great amount must be referred to individual 
peculiarity. The amount of sulphates has a decided relation to diet. 
1 Lesser, Vierteljahrsschr. f. ger. Med., 1898- 
2 “ Toxicologic der Schwefelsaure,” Wiener med. Wochen., 1862, 1863. 
3 Archivf. Anat. u. Physiol., 1864. 
