46 
ful as works of art, rivalling in the exact rendering of every 
detail, a drawing by John Ruskin, but they are so botani- 
cally correct, as to place the details of the plant before you, 
making them precious indeed to the student. The actual 
amount of illustrative work accomplished by Herbert was 
immense, there being 113 published plates, all drawn by him- 
self in addition to the 72 drawings now exhibited, or in all 
185, all sketched by his own hand, many of them crowded 
with subjects, and all bearing the stamp of perfect accuracy. 
“ On some Recent Obervations in Micro-Biology and their 
bearing on the Evolution of Disease and the Sewage 
Question,” by F. J. Faraday, F.L.S. 
N early three years ago, in a letter which appeared in the 
Manchester Guardian, of February 14, 1883, as a contribu- 
tion to a controversy on the work of Pasteur and Koch, I 
concluded as follows Pasteur is attenuating deadly para- 
sites ; before long some of his followers will evolve specific 
parasites from harmless saprophytes and in the work of 
artificially evolving, some at least of the species, such gases 
as carbonic acid will render powerful assistance.” 
Replying to this letter in the same journal, a London 
medical man spoke of the prediction as without foundation. 
I was the more surprised by such an expression of opinion 
from London, as the Times, commenting a few months pre- 
viously on a paper on Koch’s tubercle bacillus which I had 
read before the Biological Section of the British Association 
at Southampton, had been good enough to say that I had 
shown that empirical medicine had a scientific basis. In 
that paper I had argued that deprivation of free oxygen, or 
cultivation in gaseous mixtures from which the normal 
supply of free oxygen present in fresh air is absent, probably 
had an influence in converting otherwise harmless organisms 
into the parasitic bacilli of tuberculosis. I had submitted 
that the lungs of persons of hereditarily narrow-chested 
