136 VETEEINAEY TOXICOLOGY 



and clots are foujid in the heart and large vessels. There 

 is congestion of the meninges of the brain, of the lungs, 

 and other organs. 



Treatment. — Antidotes are tea, coffee, or caffeine. Strych- 

 nine is a physiological antagonist, and may be injected. 

 Ammonia as a stimulant by the mouth, and purgatives, 

 are indicated. 



Chemical Diagnosis. — The separation of alcohol from 

 tissues is easy, but its exact identification is surrounded by 

 pitfalls. Distillation of the parts from a neutral solution 

 will yield the alcohol in the first part of the distillate. If 

 the quantity permits, the concentration may be increased 

 by redistillation and dehydration with quicklime. If the 

 alcohol can thus be got free of water, the boiling point 

 (78° C.) may be observed even with very small quantities, 

 and taken along with the iodoform test, is sufficient to 

 absolutely identify. The iodoform test depends on the 

 formation of the very characteristic iodoform on gently 

 warming a dilute solution of alcohol with sodium carbonate 

 and a scrap of iodine. It is, however, given by other com- 

 pounds — e.g., aldehyde and acetone — and therefore taken 

 alone is not characteristic. In medico-legal work it is 

 valuable evidence to show that alcohol is present in the 

 blood and in the brain. 



CANTHARIDES. 



Occuprence and Uses.— The Spanish blister-fly, Can- 

 tharis vesicatoria, is found in Southern Europe, Germany, 

 and Eussia, and contains a powerful vesicant active principle, 

 cantharidine. The powdered insects form the ordinary 

 cantharides of pharmacy, and are sometimes adulterated 

 with euphorbium and the China blister-fly (Mylabris). 

 Characteristic of Spanish fly is the brilliant coppery-green 

 of the wing sheaths. The Chinese fly is larger, has two 

 orange-coloured bands and spots on the wing sheaths. 

 Cantharides, besides its use as a vesicant, is employed 



