582 FRAGMENTS OF SCIENCE. 
were exposed should include those previously alleged to be 
efficient. The conditions laid down by the heterogenist 
were accurately copied, but there was no corroboration of 
his results. Stress was then laid on the question of warmth, 
thirty degrees being suddenly added to the temperatures 
with which both of us had previously worked. Waiving 
all protest against the caprice thus manifested, I met this 
new requirement also. The sealed tubes, which hud 
proved barren in the Koyal Institution, were suspended in 
perforated boxes, and placed under the supervision of an 
intelligent assistant in the Turkish Bath in Jermyn street. 
From two to six days had been allowed for the generation 
of organisms in hermetically sealed tubes. Mine remained 
in the washing-room of the bath for nine days. Ther- 
mometers placed in the boxes, and read off twice or three 
times a day, showed the temperature to vary from a mini- 
mum of 101 degrees to a maximum of 112 degrees Fahr. 
At the end of nine days the infusions were as clear as at 
the beginning. They were then removed to a warmer 
position. A temperature of 115 degrees had been 
mentioned as particularly favorable to spontaneous gener- 
ation. For fourteen days the temperature of the Turkish 
Bath hovered about this point, falling once as low as 106 
degrees, reaching 116 degrees on three occasions, 118 
degrees on one, and 119 degrees on two. The result was 
quite the same as that just recorded. The higher 
temperatures proved perfectly incompetent to develop 
life. 
Taking the actual experiment we have made as a basis 
of calculation, if our 940 flasks were opened on the hayloft 
of the Bel Alp, 858 of them would become filled with 
organisms. The escape of the remaining 82 strengthens 
our case, proving as it does conclusively that not in the air, 
nor in the infusions, nor in anything continuous diffused 
through the air, but in discrete particles, suspended in the 
air and nourished by the infusions, we are to seek the 
cause of life. Our experiment proves these particles to be 
in some cases so far apart on the hayloft as to permit 10 
per cent, of our flasks to take in air without contracting 
contamination. A quarter of a century ago Pasteur proved 
the cause of "so-called spontaneous generation" to be 
discontinuous. I have already referred to his observation 
that 12 out of 20 flasks opened on the plains escaped 
