164 ORIGIN AND NATURE OF LIFE 



had undergone many vicissitudes before 

 Pasteur's time ; it had been affirmed or 

 denied by philosopher, naturalist, or poet 

 from age to age. 



The great Greek philosopher, Thales, traced 

 the origin of life in water, and Aristotle 

 stated the remarkable paradox that dry 

 bodies engendered animals when they became 

 damp, and moist bodies produced a like 

 effect when they dried. 



Van Helmont, a deservedly famous physicist 

 and chemist of the sixteenth century, was a 

 great believer in spontaneous generation, 

 and stated that even mice could be spontan- 

 eously generated by the simple device of 

 placing some dirty linen in a receptacle, 

 together with a few grains of wheat or a piece 

 of cheese. The same philosopher's plan for 

 engendering scorpions is naive and amusing : 

 " Scoop out a hole in a brick. Put into it 

 some sweet basil, crushed. Lay a second 

 brick upon the first so that the hole may be 

 perfectly covered. Expose the two bricks 

 to the sun, and at the end of a few days the 

 smell of the sweet basil, acting as a ferment, 

 will change the herb into real scorpions." 



A strange metamorphosis was that announ- 

 ced by an Italian, Buonanni, who found that 

 some rotten timber which he rescued from 



