
OTHER NEW EXPERIMENTS 175 
after being allowed to cool, the chloride of calcium 
is washed from its exterior. 
The tube and the solution of potash, thus purified 
by heat, is next to have its top cut off 
above the plug of cotton-wool, and 17. 
or 18 cubic centimetres of the boiled 
urine are to be aspirated into the 
side of the tube (B) not containing 
the potash. 
The next directions are these :— 
Plunge the tube into bowling water 
and heat 2t to100 C. for ten minutes. 
Allow the tube to cool. | 
Cause 15 centimetres of the urine 
to pass into the branch (A) containing 
the potash. Thus 2 to 3 cubic centi- , 





metres of the doubly boiled urine will : 
remain in B, in order to serve as a Fic. 8. 
control, and show that the urine has _ pasteur’s double 
been thoroughly sterilised by the tem- tube. 
perature to which it has been exposed, which, 
Pasteur repeats, is always the case when dealing 
with an acid urine. 
Place the tube in a stove at 50 C. 
Result : Never an appearance of. micro-organisms. 
M. Pasteur repeated to me in his laboratory, in 
the presence of M. Chamberland, and even wrote 
the statement on a piece of paper with a blue pencil, 
that, operating as I did, organisms were “le plus 
souvent” to be found in the fluids. He had, in fact, 
twice said the same thing, in his replies to the Notes 
