Feb. i8. 1918 Efficacy of Some Anthelmintics 411 



sheep were used and treated by drenching with increasing doses of gaso- 

 line in milk as recommended by Coffey {19 13). The dosage given was 

 15, 22, and 30 mils in 236.6 mils of milk on the first, second, and third 

 days, respectively. The same dose was given to each animal. 



The first sheep passed no stomach worms and had none on post- 

 mortem examination, so the efficacy of the treatment in this case is 

 undetermined. A few hookworms only were passed. The second 

 sheep, which was lightly infested with stomach worms, passed none, but 

 passed a few specimens of hookworms and nodular worms, forming a 

 small percentage of the total number present. 



In this experiment, although the sheep received much larger doses 

 than in the previous experiments and the medicine was given in a drench, 

 there were no evidences of pneumonia or gastritis. 



Considering the three experiments with gasoline as a whole, involving 

 the use of nine experiment animals, the writers find that this treatment 

 removed over one-fourth of the stomach worms present and had some 

 slight efficacy for hookworms and nodular worms. This compares very 

 unfavorably with the efficacy of copper sulphate for stomach worms 

 when given in solution. The gasoline treatment has also the further 

 disadvantages that it must be given three times, and in a vehicle such 

 as linseed tea or milk, which is an additional expense. There is also the 

 possibility of causing traumatic pneumonia, although the subsequent 

 experiments with this drug indicate that gasoline is not necessarily 

 more dangerous as a drench than is copper sulphate. 



PETROLEUM BENZIN 



For worms in sheep. — As already stated. Stiles (1901) was favorably ' 

 impressed with the use of gasoline as a vermifuge in spite of certain objec- 

 tions that he notes. It was suggested by Dr. B. H. Ransom, Chief of the 

 Zoological Division, Bureau of Animal Industry, that our failure to get 

 more satisfactory results might be due to the difference in the commercial 

 gasoline of the present day and that used by Stiles. It was recalled that 

 in 1 90 1, when Stiles conducted his experiments, the automobile industry in 

 this country was in its infancy, and there was little demand for gasoline. 

 Consequently the petroleum distillers included only the most volatile 

 hydrocarbons in gasoline, reserving the heavier fluids for kerosene, their 

 principal product. At the present day, with conditions reversed, the 

 distillation temperatures of gasoline have been greatly extended, with a 

 consequent increase in the specific gravity and lessening of volatility. 



In order to determine whether the lessened volatility of the present- 

 day gasoline was related to its inefficacy as a vermifuge, a test was made 

 by the junior writer of petroleum benzin, U. S. P. This product, dis- 

 tilled between 45° and 60° C, represents only the most volatile hydro- 



