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W. L. RHOADS. 
them and the infusoria might come from fungi through develop¬ 
ment by hetrogenesis. Would this not lead us into the belief 
that the light giving forces are in themselves spontaneous gener¬ 
ators of disease from germs pre-existing ? Yet we are told by 
scientists of to-day that light is a most potent factor in the 
destruction of ptomaines. Prof. Ward of England, going so far 
as to assert after experimenting with electric light that the light 
rays, and not the heat rays, are destructive to bacteria and that 
among the different colored rays the blue rays are the most 
effective for this purpose, while another scientist claims the 
yellow or orange rays to be most conducive to the propagation 
of bacteria, have not heard of their growth in total darkness. 
Anthrax was formerly attributed to a minute microscopic fly, 
which, on account of their greatn umber, formed a blue mist in 
the atmosphere. This was the first disease to have conclusive 
proof offered of its germ origin. The question of its etiological 
relation was placed on a scientific basis by inoculation with the 
pure culture of anthrax bacillus. To Pasteur belongs the credit 
for experiment or preventive inoculation Avith his attenuated 
virus in many diseases. Animals inoculated with cultivated 
bacillus show immunity from disease when inoculated with the 
deadly wild germ. The cause for this has not been as yet 
determined. 
Though Matschnikoff in 1884 advanced the theory that the 
white corpuscles eliminated the bacilli from the blood, germs as 
a rule are very tenacious of life, and, while light is now believed 
to destroy them, it has been but a short time since scientists told 
us that boiling would destroy them,yet they have been known to 
withstand as low as ioo° C. and as high as no° C., the ripe 
spores showing the greater powers of resistance. They flourish 
best in moisture, at a temperature of about 35 0 C. and readily 
live on remains of dead organisms or truly parasitical are 
nourished direct from a living body; as a rule their ends are 
rounded and they frequently present a beaded appearance if not 
isolated. Though their length may vary, they are always e\ T enly 
proportioned. I trust the future will give such magnifying 
