174 THE EVOLUTION OF LIFE™ 
before them in my absence, which, I think, was a 
wrong course. We each ought to have had an 
opportunity of seeing the other’s experiments per- 
formed before the Commission ; and, evidently, the 
intention was that M. Pasteur should be present 
during the performance of mine. 
As the Commission proved an abortive one, on 
the following Monday (July 23, 1877) M. Pasteur 
submitted a Note on the subject of his experiment 
to the Academy. It concerned the actual experi- 
ment which he had performed before the Commis- 
sion, and is to be found in the Comptes Rendus 
for the date mentioned. The experiment is a very 
ingenious one, and but for one fatal defect, which I 
shall presently indicate, ought to have led to a 
successful reproduction of my results. 
I will first describe the details of the experi- 
ment, and we can then look to the question of 
interpretation. 
Some urine contained in a purified vessel is boiled 
for ten minutes, and its degree of acidity is tested 
when it has cooled. 
A solution of potash sufficient for the neutralisation 
of 15 cubic centimetres (half an ounce) of the urine 
whose acidity has been tested is to be introduced into 
one branch (A) of the double faméé tube, plugged 
with cotton-wool, such as is shown in the figure. 
The tube is to be hermetically sealed above the 
cotton-wool plug, and the two narrow prolongations 
being already sealed, the closed tube containing the 
solution of potash is placed in a chloride of calcium 
bath and heated to 110° C. for ten minutes. Then, 
