CORROSIVE OR IRRITANT POISONS 49 



relish, and no season passes without deaths resulting from such compounds 

 being left within their reach. Weed -killer is poured upon garden-paths 

 and carriage-drives, and animals have been known to succumb after eating 

 the weeds before wet weather has washed it into the soil. Refuse paints, 

 containing emerald green, Scheele's green, Brunswick green, where cast 

 upon pasture land in manure, are sometimes followed by fatal results. The 

 death of some valuable horses was caused in one instance by a tin of this 

 fluid being upset and becoming mixed with the corn. Arsenic is used also 

 as a dressing for wheat, and a poison for vermin, and less frec]uently as 

 a cure for warts and foot-rot. 



Symptoms. — Although there is much difference in the susceptibility 

 of animals, as proved by the experiments of Hertwig, Percival, Gerlach, 

 and others, the action of this poison is largely governed by the condition of 

 the stomach as to the presence or absence of food. The quantity of food in 

 the stomach has also a great influence in delaying the toxic effects of the 

 drug. In one of Percival's experiments upon a glandered horse an increas- 

 ing daily dose was given with food until, on the seventeenth day, it had 

 reached 380 grains, making a total of 7 ounces in all. Even this large 

 quantity failed to produce any physiological effects. On the other hand, 

 the fatal effects of much smaller quantities were seen in the case of eleven 

 cart-horses which were poisoned at Edgware by drinking out of a bucket 

 that had previously been used for sheejD-dip, one of the animals dying in 

 ten minutes, and several more within the hour. The quantity taken by 

 each horse in this case must have been small, but there is reason to think 

 that the empty condition of the stomachs had rendered them more sus- 

 ceptible of its action. 



Poisoning by arsenic is sometimes very sudden, and at others slow and 

 progressive; the one being spoken of as acute poisoning, the other as 

 chronic or cumulative. In the chronic there may be an appearance at first 

 of improved tone, shiny coat, strong pulse, and good spirits; these being 

 maintained by what would be called the " arsenic habit " but for the fact 

 that it is involuntary on the part of the animal. After using it for a time it 

 fails of effect, and the carter is tempted to increase the dose, until presently 

 appetite fails and is ultimately lost, the coat stares, shivering-fits follow, 

 colicky pains set in, and are succeeded by purging, prostration, imper- 

 ceptible pulse, staggering, falling, and death. In the acute form of the 

 disease there is sudden and desperate illness without premonitory signs, 

 those even who are quite unaccustomed to animals recognizing the rapid 

 approach of death by the haggard countenance, quick breathing, and violent 

 trembling of the body, and general distress. The skin is bathed in sweat, 

 the ears and legs are very cold, the eyes are protruding and bloodshot; 



Vol. III. 69 



