IMMUNITY FROM CONTAGIOUS DISEASES. 
315 
bnt it certainly explains facts which have not been explained in 
any other way ; and, if it is to be overthrown, I presume this 
will be accomplished by bringing forward some facts with which 
it cannot be reconciled and by developing a different theory 
which, while it explains the new facts, will not contradict the old 
ones. 
It seems unnecessary for me to answer the charge that my 
theory is too narrow, for Dr. Curtiss no sooner makes it than he 
sets himself about whittling down even this narrow theory, and 
soon asserts that a part of it—the part which assumes the acquired 
ability of the cells to resist the poison—is all that there is to the 
whole question of immunity. The inconsistency of this part of 
his argument is too apparent to need any criticism. 
Now a final word as to the utility of the studies of immunity, 
and I hope I shall be permitted to withdraw from the discussion. 
I shall not attempt to conceal my astonishment that a professor of 
hygiene can be found in this country who deliberately writes that 
“ the study of physically acquired immunity from disease is in. 
teresting only as a means or end of scientific accomplishment^ 
and is of no great practical value. . . . Why not destroy the 
microbe before it attacks the man, and gain the immunity by this 
means? . . . Immunity from disease gained by costly combat 
with poisonous microbes is the method of nature without intelli¬ 
gence. The method is not worth imitation except provisionally.” 
That is to say, vaccination for the prevention of small-pox, the 
method of all others which is relied upon in every civilized coun¬ 
try to hold this disease in check, a is of no great practical value, 
and is not worth imitation except provisionally.” How is it, I 
would like to ask, that we still rely upon vaccination to prevent 
small-pox if it could be so easily combated by destroying the 
microbe before it attacked the man ? Why is it that we at the 
present day, in the United States, are losing every year 20,000 
human lives from scarlet fever, 45,000 from diphtheria, 14,000 
from whooping-cough, 11,000 from measles, and 120,000 from 
tuberculosis, and all of these germ diseases ? Is it not because the 
destruction of the germ before it attacks the man has been found 
impracticable and, in the present state of society, impossible % 
