24 BOARD OF AGRICULTURE. 



gardens and fields, or dangerous and destructive animals in 

 your forests. All living things can be exterminated, — the 

 disease germ as well as the weed or animal, — and there- 

 fore the utility of stamping out such plagues, whenever this 

 is possible. Our studies of germs come to our assistance 

 even here, for we are learning what formerly we did not 

 suspect, that what may be a good diseufectant in one disease 

 may be useless in another. At present we test the effect of 

 such agents upon the germ of a particular disease before we 

 trust them implicitely as disinfectants. Carbolic acid, in 

 solutions of sufficient strength, destroys almost all varieties of 

 disease germs, but if this is diluted until the mixture con- 

 tains less than one per cent., it is no longer reliable. It is 

 not many years since we trusted implicitly in the disinfect- 

 ing powers of carbolic acid, and we troubled our heads very 

 little as to the strength in which it was used, or the liquids 

 with which it was diluted, though these are essential points. 



There are some diseases, such as fowl cholera, swine 

 plague, black quarter and anthrax, which we cannot at pres- 

 ent attempt to stamp out, and for these a safe, simple and 

 effective system of vaccination would be a great boon. But 

 there is much yet to be done before the viruses of these dis- 

 eases can be safely manipulated and distributed over a great 

 country like this, to be used by every farmer and stock-raiser 

 who needs them. Details must be worked out, the opera- 

 tions must be simplified, and even new methods of attenua- 

 tion and cultivation must be devised to meet conditions 

 essential to some of them. There is too much at stake to 

 allow of any blunders to be made, and it would be inexcus- 

 able for us to recommend practices before they have been 

 thoroughly and systematically tested. 



I have endeavored to present to you, in outline, the 

 present aspect of the problems relating to the contagious 

 fevers of animals, — I might say of men as well, — in 

 order that you might understand what we are trying to ac- 

 complish at the Department of Agriculture in Washington. 

 The losses from such plagues amount to many millions of 

 dollars every year, and Congress has wisely decided that a 

 email amount of money should be expended annually in their 

 study, so that the vast stock-raising interests of this coun- 



