M 
220 : Scientific News. [ February, 
was small, the carbonic acid would at once be taken up, so that 
it did not accumulate in the immediate vicinity of the breathing 
apparatus.—English Mechanic. 
— In an address delivered lately at Preston, after distributing 
the prizes to the students of the Harris Institute, Professor 
Tyndall spoke of the three great discoveries which in after time 
will be regarded as the glory of the present age, vis: those of the 
conservation of energy, the principle of evolution, and the germ 
theory of disease. The germ theory of disease in its earliest 
slimmerings appeared centuries ago; but William Budd was the 
first to see further than his contemporaries, and his grand gener- 
alization has been confirmed by experiment. So long ago as 
1817 Schwann demonstrated that putrifaction was the work of 
living organisms, and in 1863, Pasteur followed with his far more 
elaborate researches. A high tribute was paid to Koch’s re- 
searches. The immunity enjoyed by the vaccinated, Tyndall 
accounts for on the supposition that contagia being living things, 
demand certain elements of life, and when those are exhausted 
they can no longer live. To exhaust a soil, then, a parasite less 
vigorous and destructive than its virulent representative may 
suffice, and once the soil is exhausted the virulent type is power- 
less to injure. Such in substance is the germ theory of disease. 
—At the Newport meeting of the National Academy of 
Sciences, Mr. Fairman Rogers referred to Mr. Muybridge’s ex- 
periments made last summer on the motions of animals by instan- 
taneous photography. No especially new system is used, but 
_— Professor Bickmore, of the American Museum of Natural 
History, will give a course of ten lectures for the benefit of such 
teachers in the public schools as are required to deliver object 
lessons upon botany and zodlogy. The first six lectures will be 
- a to human physiology and anatomy. The lectures are all 
pic views, and in order to make them 
