300 BRIEF HISTORY OF BACTERIOLOGY UP TO 1881 



practical results, since FraD9ois Appert, in 1810, applied 

 them to the preserving of fruits, meats, etc., and in a sense 

 started the modern canning industry. Spallanzani was the 

 first to boil an infusion to kill the ''germs'' in it, the first to 

 sterilize purposely by boiling, and the first to seal to keep the 

 germs out. 



From Spallanzani to Schultze there were no further 

 experiments to prove or disprove spontaneous generation. 

 Schultze, in 1836, attempted to meet the second objection 

 to Spallanzani's experiment, i. e., the exclusion of air, by 



Fig. 171. — Schultze's experiment. The set of bulbs next to the face con- 

 tained KOH and the other set concentrated H2SO4. Air wais drawn through 

 at frequent intervals from May until August, but no growth developed in 

 the boiled infusion. 



drawing air through his boiled infusions, first causing it 

 to bubble through concentrated sulphuric acid to kill the 

 *'germs"(Fig. 171). His flasks fortunately showed no growths, 

 but his critics claimed that the strong acid changed the 

 properties of the air so that it would not support life. This 

 experiment of Schultze's, though devised for a different 

 purpose, was really the first experiment in the use of chemical 

 disinfectants, though Thaer (page 311) had used chemicals in 

 a practical way. Schwann, in 1837, modified this experi- 

 ment by drawing the air through a tube heated to destroy 

 the living germs (Fig. 172) . His experiments were successful, 



