EXPERIMENTS WITH BISULPHIDE OP CARBON. 



27 



dogs, and 30 cubic centimeters or 2 tablespoonfuls for spermophiles 

 and pocket gophers) should be poured upon a bunch of rags or waste, 

 which should be immediately placed within the mouth of the burrow, 

 and the hole closed. 



EXPERIMENTS WITH BISULPHIDE OF CARBON. 



A few simple experiments have been made in killing small mammals 

 with bisulphide of carbon. The species upon which the experiments 

 were tried were such as could be readily x>rocured — skunks, prairie 

 dogs, striped spermophiles, pocket gophers, and the common rat. In 

 most cases far too much of the liquid was used, but the object was 

 mainly to determine the quantity necessary to kill animals of various 

 sizes. The animal after being caught in a trap, was fastened by a string 

 and allowed to enter its hole. A measured quantity of liquid bisulphide 

 of carbon was then poured into the hole, the mouth of which was usually 

 covered, and the time required for the animal's death noted. By means 

 of the string they were drawn out of the holes, and if not dead, re- 

 placed until they were. Following are some of the experiments : 



Wichita Falls, Tex., August, 1892. — (1) A prairie dog, fastened by a 

 strong cord, was allowed to enter its hole. It carried down 12 feet 10 

 inches (3.9 meters) of cord. The hole measured 4 inches (100 milli- 

 meters) in diameter. I poured in 49 cubic centimeters of bisulphide 

 (about 3 tablespoonfuls), and in eight minutes drew out the prairie dog, 

 dead. 



(2) Another prairie dog fastened by a cord was allowed to enter its 

 hole 8 feet 3 inches (2.5 meters). The hole was 5f inches (145 milli- 

 meters) in diameter. I poured in 49 cubic centimeters of bisulphide 

 and in five minutes drew out the prairie dog, dead. 



(3) Another was allowed to go down its hole about 10 feet (3.04 

 meters). I poured in 49 cubic centimeters of bisulphide, and in five 

 minutes the prairie dog was apparently dead, but caught in the hole, 

 and I broke the string in trying to draw it out. 



(4) Another prairie dog with string attached entered its hole 4 feet 

 3 inches (1.3 meters). Poured in 49 cubic centimeters of bisulphide, 

 and in six minutes drew out the dead prairie dog. 



(5) Another with its foot in a trap went down the hole 14 inches 

 (355 millimeters). I poured in 29 cubic centimeters (2 tablespoonfuls), 

 of bisulphide and covered the hole. In five minutes the prairie dog 

 ay as still alive. The gas had passed by it and filled the lower part of 

 the hole, but had not filled it high enough to reach the prairie dog. 

 From the effects of the gas it was nicely anaesthetized and did not 

 revive for two or three hours. 



(6) A Striped Spermophile (S. tridecemlineatus) was allowed to go 

 down its hole 14 inches (355 millimeters). Poured in some bisulphide, 

 and in six minutes drew out the spermophile dead. 



(7) Caught a skunk by one foot in a steel trap. It had crawled 



