46 KILLING WOODCHUCKS WITH CARBON BISULPHIDE 



treated a number of holes with the substance. So far as 

 known the results were all successful. In one case the bur- 

 row was dug out and a large woodchuck was found dead in a 

 circular chamber, about five feet from the mouth of the burrow 

 and two feet below the ground vertically. In another case a 

 mouse hole connecting with a woodchuck burrow which had 

 been treated with the bisulphide was dug out and three white- 

 bellied field mice were found dead, showing that the poison- 

 ous vapor had followed along the comparatively small burrow 

 of the mouse. 



In 1898 a few more experiments were made, an ounce of 

 the liquid being poured upon a wad of old burlap loosely 

 wound around the end of a stick in such a way that when the 

 stick was pushed down into the burrow and then withdrawn 

 the burlap would remain in the hole. The holes, of course, 

 were stopped up and two days later they had not been opened, 

 so that it was pretty sure that the animals were dead inside, 

 as there was evidence of their having been, very recently, 

 present. 



In 1899 experiments were continued by Mr. R. A. Cushman 

 with similar successful results. On July 27 a hole was treated 

 at 9 130 a. m. with two-thirds of an ounce of bisulphide of 

 carbon just after a woodchuck had been seen to enter it. The 

 afternoon of the next day the hole had not been uncovered, so 

 that it was safe to assume that there was a dead and buried 

 woodchuck within it. 



Another burrow having two entrances was treated the morn- 

 ing of July 27 with about an ounce of bisulphide. At 2 p. m. 

 the next day neither entrance had been uncovered. A third 

 burrow having three entrances treated at the same time with 

 nearly an ounce of bisulphide to each entrance had not been 

 uncovered when visited on the afternoon of the next day. A 

 fourth burrow having four entrances was treated at 10 a. m. 

 July 27, nearly an ounce of the liquid being used in each 

 entrance which was, of course, covered with earth immedi- 

 ately after'treatment. At 2 p. m., July 28, none of the en- 

 trances had been uncovered. 



On July 29, 1899, two burrows were treated; one having 

 only one entrance was covered at 9:30 a. m. after treatment 



