(j 8 POISONS : THEIll ^REFECTS AND DETECTION. [§§ 69 , 70 . 
University College. —In this museum will be found an exquisite preparation of the 
effects of sulphuric acid. The mucous membrane of the oesophagus is divided into 
small quadrilateral areas by longitudinal and transverse furrows : the stomach is 
very brown and covered with shreddy and filamentous tissue ; the brown colour is 
without doubt the remains of extravasated and charred blood. 
No. 6201 is a wax cast representing the stomach of a woman who died after taking 
a large dose of sulphuric acid. A yellow mass was found in the stomach ; there are 
two perforations, and the mucous membrane is entirely destroyed. 
§ 69. Chronic Poisoning by Sulphuric Acid. —Weiske 1 has experi¬ 
mentally proved that lambs, given for six months small doses of sulphuric 
acid, grow thin, and their bones, with the exception of the bones of the 
head and the long bones, are poor in lime salts; the muscles also are 
poor in the same constituents. Kobert 2 thinks that drunkards on the 
Continent addicted to “ Schnapps,” commonly a liquid acidified with sul¬ 
phuric acid to give it a sharp taste, often show typical chronic sulphuric 
acid poisoning. 
Detection and Estimation of Free Sulphuric Acid. 
§ 70. The general method of separating the mineral acids is as fol¬ 
lows : the tissues, or matters, are soaked in distilled water for some time. 
If no free acid is present, the liquid will not redden litmus paper, or give 
an acid reaction with any of the numerous tinctorial agents in use by the 
chemist for the purposes of titration. After sufficient digestion in water, 
the liquid extract is made up to some definite bulk and allowed to sub¬ 
side. Filtration is unnecessary. A small fractional part (say, for example, 
should the whole be 250 c.c., yi^-th or 2*5 c.c.) is taken, and using as an 
indicator cochineal or phenolphthalein, the total acidity is estimated by a 
decinormal solution of soda. By this preliminary operation, some guide 
for the conduct of the future more exact operations is obtained. Should 
the liquid be very acid, a small quantity of the whole is to be now 
taken ; but if the acidity is feeble, a larger quantity is necessary, and 
sufficient quinine then added to fix the acid—100 parts of sulphuric acid 
are saturated by 342 parts of quinine monohydrate. Therefore, on the 
supposition that all the free acid is sulphuric, it will be found sufficient 
to add 3-5 parts of quinine for every 1 part of acid, estimated as sul¬ 
phuric, found by the preliminary rough titration ; and as it is inconveni¬ 
ent to deal with large quantities of alkaloid, a fractional portion of the 
liquid extract (representing not more than 50 mgrms. of acid) should be 
taken, which will require 175 mgrms. of quinine. 
On addition of the quinine, the neutralised liquid is evaporated to dry¬ 
ness, or to approaching dryness, and then exhausted by strong alcohol. 
The alcoholic extract is, after filtration, dried up, and the quinine sul¬ 
phate, nitrate, or hydrochlorate, as the case may be, filtered off and 
1 H. Weisko, Journ.f. Landivirthsch., 1887, S. 417. 
2 Lehrbuch der Intoxicationem, S. 210. 
