504 poisons : their effects and detection. [§§ 661, 662. 
pain about the loins, and also irritation of the bladder. There was no 
sexual excitement. 
§ 661. Post-mortem Appearances. —In a French criminal case, in 
which a man poisoned his step-brother by giving cantharides in soup, the 
pathological signs of inflammation’of the gastro-intestinal tract were 
specially evident, the mouth was swollen, the tonsils ulcerated, the 
gullet, stomach, and intestines were inflamed, and the mucous membrane 
of the intestines covered with purulent matter. In another case there 
was an actual perforation 3 inches from the pylorus. The inflammatory 
appearances, however, are not always so severe, being confined to 
swelling and inflammation without ulceration. In all cases there has 
been noted inflammation of the kidneys and urinary passages, and this 
is seen even when cantharidin is administered to animals by subcuta¬ 
neous injection. In the urine will be found blood and fatty epithelial 
casts, as well as pus. The contents of the stomach or the intestines will 
probably contain some remnants of powdered cantharides, if the powder 
itself has been taken. 
§ 662. Tests for Cantharidin, and its Detection in the Tissues, 
etc. —The tests for cantharidin are—(1) Its form, (2) its action in 
the subliming cell, and (3) its power of raising a blister. 
The most convenient method of testing its vesicating properties is to 
allow a chloroformic solution of the substance supposed to be cantharidin 
to evaporate to dryness, to add to this a drop of olive oil (or almond oil), 
and to take a drop up on the smallest possible quantity of cotton-wool, 
and apply the wool to the inside of the arm, covering it with good oilskin, 
and strapping the whole on by the aid of sticking-plaster. In about an 
hour or more the effect is examined. The thin skin of the lips is far 
more easily blistered than that of the arm, but the application there is 
inconvenient. 
Dragendorff has ascertained that cantharidin is not present in the 
contents of a blister raised by a cantharides plaster, although it has been 
found in the urine of a person treated by one ; and Pettenkofer has also 
discovered cantharidin in the blood of a boy to whose spine a blister had 
been applied. 
The great insolubility of cantharidin in water has led to various 
hypotheses as to its absorption into the system. It is tolerably easily 
dissolved by potash, soda, and ammonia solutions, and is also taken up in 
small proportion by sulphuric, phosphoric, and lactic acids. The result¬ 
ing compounds quickly diffuse themselves through animal membranes. 
Even the salts with lime, magnesia, alumina, and the heavy metals are 
not quite insoluble. A solution of salt with cantharidin, put in a 
dialysing apparatus, separates in twenty-four hours enough cantharidin 
to raise a blister. 
Cantharidin has actually been discovered in the heart, brain, muscles, 
