no THE POPULAR SCIENCE MONTHLY. 



resulting in the rapid destruction of all. While this is experi- 

 mental work, and may not invariably give the satisfactory results 

 to be wished for, it illustrates in a striking manner one way in 

 which science is working in the interests of agriculture. 



In 1887 what is known as the gypsy moth ( Ocneria dispar) was 

 discovered in eastern Massachusetts. This insect was originally 

 brought to Massachusetts from France, where it is exceedingly de- 

 structive to vegetation, and especially the foliage of trees. When 

 first found in Massachusetts its character was not known by the 

 finder, but when later examined by Prof. Fernald, of the State 

 Agricultural College, he, knowing its nature, at once began an in- 

 vestigation to ascertain how much of a foothold it had in the 

 State. It was located in numerous towns. The Legislature was 

 advised of the dangerous character of the insect. A State law 

 was enacted to provide against the depredations of the gypsy 

 moth. Several commissioners were appointed and money appro- 

 priated to eradicate the insect. During the entire growing season 

 of 1892 bands of men were engaged in destroying this insect in 

 its various forms, and every effort is being made to prevent its 

 further increase. 



Perhaps the most serviceable labor given by science to the 

 cultivator, in its application to insects, is the invention and per- 

 fection of insecticides. A great number of experiments have 

 been conducted in agricultural colleges and experiment stations 

 over the country with solutions and powders with which to kill 

 injurious insects. Arsenic in different preparations, carbolized 

 plaster, kerosene, hellebore, pyrethrum, hot water, and Bordeaux 

 mixture have been in use and tested in many ways, so that, as a 

 result of this work, standard insecticides can be recommended to 

 farmers generally, which may be easily made at home out of sim- 

 ple ingredients. What is termed the kerosene emulsion is per- 

 haps, all things considered, the best general insecticide in use. 

 This may be made as follows, following Cook's directions : * Dis- 

 solve in two quarts of water one quart of soft soap or one fourth 

 pound of hard soap, by heating to boiling ; then add one pint of 

 kerosene oil, and stir violently for from three to five minutes. 

 This can then be diluted with twice its bulk of water for use. 

 This emulsion will destroy lice on both live stock and plants. 



Finally, we have in the United States nearly fifty experiment 

 stations where trained men are working in the interests of agri- 

 culture — men whose one aim is to conduct research of benefit to 

 mankind. Considering this fact, and that numerous scientists 

 outside of the stations are also engaged in a class of work that of 



* Michigan Agricultural Experiment Station, Bulletin 76, October, 1891, p. 5. Kero- 

 sene emulsion. 



