450 HEARINGS BEFORE COMMITTEE ON AGRICULTURE. 
Mr. Apams. There may be some qualification surrounding this 
statement. 
Mr. Grarr. There was another conclusion, and that was the fertili- 
zat on of soil by manure or by the artificial fertilizers which are made 
contributed to the soil no lasting additional chemical content, and that 
it produced no permanent result in the growth of the immediate crop; 
that the utmost it would do, perhaps, was to stimulate the growth of 
the plant when it first began to germinate; and that is certainly con- 
trary to the general view of the practical farmer. 
Secretary Witson. Yes; I have gone all over that with Doctor 
Whitney. The growth of crops by chemical or what are known as 
commercial fertilizers alone will eventually ruin any soil, because the 
organic matter is oxidized or burnt out of the soil and the soil becomes 
loose and subject to be carried away with the waters in the summer 
time and will not retain moisture. 
Mr. Lams. That is true; we all know that. 
Secretary Witson. Yes; there are limitations to all those statements. 
I do not pretend to conclude with regard to Doctor Whitney’s Bulle- 
tin No. 22; but we will have it looked into by competent authority if 
it is thought best to doit. Ihave had it in my mind. Doctor Whit- 
ney is doing such good work that we can still find work for Doctor 
itney. 
Mr. Have The discussion of this Bulletin 22 will be productive 
of good results, whatever— 
Secretary Witson. I think so. You had a discussion of that at one 
time in regard to Doctor Salmon and his hog-cholera investigations 
by a man in Nebraska. Doctor Salmon is still here, and I do not 
know what has become of the man in Nebraska. 
Mr. Lams. That leads me to make a new inquiry of you, Mr. 
Secretary. I have received letters saying the Government is making 
serum to destroy blackleg, and trying to interfere with private 
enterprise. I would like to hear from you on that. 
Secretary Witson. Blackleg is a disease that affects young animals, 
mostly calves; sometimes yearlings, and, very rarely, 2 year olds. 
The people had great difficulty in getting serum that was powerful 
enough to treat it. We make it here for probably a tenth of a centa 
dose; and we send out, say, a million and a half doses a year, free to 
the people, and the result is that wherever we send it blackleg is dis- 
appearing. We are pushing this work with the theory that if we can 
prevent black-leg it will die out. 
It is the same with rabies. If you muzzle every dog in the District 
of Columbia and allow no other dog to come in rabies will not come 
in. You could not do that. The love for the pup is stronger than the 
love for man, woman, or child in the District of Columbia, and dogs 
can not be muzzled here. That is the theory on which we are tryin 
to experiment with blackleg, and we are succeeding. The day sfould 
come when there will not be a particle of blackleg in the United States. 
Mr. Burteson. As I understand it, Mr. Secretary, these laboratories 
are maintained by the Bureau of Animal Industry and its manufacture 
costs a mere trifle. 
Secretary Witson. Yes. Of course we are interfering with the 
trade, and if we destroy blackleg in cattle we will destroy their trade 
in blackleg serum altogether. The economic question is whether we 
should maintain blackleg for the benefit of these manufacturers. 
