242 PROFESSOR RUTHERFORD ON THE 
viscous fluid with grey flakes; thus affording evidence of strong purgation. 
The vascularity of the mucous membrane was decidedly increased. 
Result of Experiments with Calomel mixed with Bile.—The biliary secretion — 
in Experiment 76A was so regular, and the doses of calomel so graduated, that 
its result may be regarded as conclusively showing, that calomel when mixed 
with bile and placed in the duodenum, does not excite the liver, although it 
powerfully stimulates the intestinal glands. The addition of bile to the calomel 
made therefore no difference in the result. 
As is well known, M1AnLe (Chimie Appliquée) ascribed all the effects of 
calomel, and other mercurial preparations, to the production of mercuric 
chloride, by the action of the alkaline chlorides in the secretions of the alimen- 
tary canal, more especially in the gastric juice. This theory has, however, been 
strongly opposed by BucHHEIM, CETINGER, and WINCKLER (referred to by Woop 
in Op. xi. p. 330), on the grounds that, at a temperature so low as that of the 
body, calomel undergoes no transformation into mercuric chloride in a solution 
of alkaline chlorides. Nevertheless, one must remember that the gastric juice 
contains free hydrochloric acid. The amount is only 0°02 per cent. in the juice 
of man, mixed with saliva: in that of the dog, the amount is 0°031 per cent. 
(C. Scumipt). When Mr1Auze wrote, the free acid of the gastric juice was 
thought to be lactic; therefore, the effect of very dilute hydrochloric acitl on 
calomel, at the body temperature, has not hitherto been investigated. As no 
conclusion could be legitimate in the absence of definite information on this 
point, we performed the following experiment :— 
Experiment 77.—Calomel was washed with ether, the filtrate tested with 
caustic potash, and proved to contain no mercuric chloride. Of the calomel— 
thus ascertained to be pure—we placed three grammes in 500 cc. distilled 
water containing 0°02 per cent. anhydrous hydrochloric acid,and submitted the 
whole to a constant temperature of 100° Fahr.—the temperature of the stomach 
—for thirty-six hours. The fluid was then filtered, concentrated, and tested 
with sulphuretted hydrogen. A distinct precipitate—first white, then changing 
to yellow, and finally to black—was obtained, thus proving the presence of cor- 
rosive sublimate. Judging from the precipitate, the amount was considerable ; 
but a large quantity of calomel had been employed, and it had been acted on 
by the acid for a lengthened period. We repeated the experiment, using the 
same amount of calomel, and acid fluid, but keeping it only seventeen hours at 
the temperature of the body. The fluid was then filtered, the filtrate evapo- 
rated, the residue dried and weighed, and it was found that three grammes of 
calomel had yielded 17 milligrammes of mercuric chloride. Under similar cir- 
cumstances, 5 grains of calomel—the ordinary dose for a man—would, if digested 
seventeen hours with about 50 cc. acid fluid, have yielded =}; grain mercuric 
chloride. Whether or not so minute a quantity of the latter substance is likely 
