6 T. W. E. DAVID. 
pounded in water, and the water is then examined microscopically. 
If “corpuscles” are found in it, the whole of the eggs of this 
moth and the linen on which they are laid are burnt; if no 
corpuscles are found, the eggs are kept to be, in due time, hatched 
and yield healthy silkworms.” 
Later came Pasteur’s great discovery, that a vaccinating virus 
could be formed by attenuating solutions containing specific 
bacilli. Thus a mild form of the disease being communicated to 
the animals vaccinated with such virus, they were rendered 
immune from the attacks of the non-attenuated organism. This 
method was subsequently proved by him to be a remedy for fowl 
cholera, swine erisipelas, and anthrax. It will be within the 
memory of most of us, that when the Government of New South 
Wales offered a prize of £25,000 for a satisfactory scheme for the 
extermination of the rabbit, Pasteur claimed that such an end 
might be gained by inoculating the rabbits with the microbes of 
fowl-cholera. Exhaustive experiments at Rodd Island conducted 
by Pasteur’s pupil, Dr. Loir, and by Dr. Katz, seemed to show 
that the disease was not very infectious in the case of rabbits, 
and as it was uncertain that it was readily communicable from 
one rabbit to another, but certain that it would cause great 
mortality among the Australian birds Pasteur’s proposal was not 
accepted. This country, however, together with the whole 
civilized world, owes Pasteur a deep debt of gratitude, not only 
for his own discoveries, brilliant and numerous as they have been, 
but also for those which have resulted directly from his teaching. 
Working on the same lines of research as those pursued by 
Pasteur, Héricourt and Richet made the very important discovery 
that the fluids and cells of animals which have been rendered 
immune by vaccination have themselves become vaccines and are 
capable of protecting also other animals. Serum-therapy is based 
on this principle, and Professor Anderson Stuart! estimates that 
the number of human lives saved in New South Wales alone by 
1 Antitoxic Serum for the Cure of Diphtheria.—Report by Board of 
Health, by Authority, Sydney, 1895, p. 1. 
| 
| 
| 
. 
| 
| 
| 
a 
