A HISTORY OF SCIENCE 



struments are required to make these shavings whose 

 curls are in no wise uniform, but seemingly casual ; and 

 what is more remarkable, bodies that before seemed 

 unelastic, as beams and blocks, will afford them." l 



Although this explanation of the composition of 

 the air is most crude, it had the effect of directing 

 attention to the fact that the atmosphere is not " mere 

 nothingness," but a "something" with a definite 

 composition, and this served as a good foundation for 

 future investigations. To be sure, Boyle was neither 

 the first nor the only chemist who had suspected that 

 the air was a mixture of gases, and not a simple one, 

 and that only certain of these gases take part in the 

 process of calcination. Jean Rey, a French physician, 

 and John Mayow, an Englishman, had preformed 

 experiments which showed conclusively that the air 

 was not a simple substance ; but Boyle's work was bet- 

 ter known, and in its effect probably more important. 

 But with all Boyle's explanations of the composition 

 of air, he still believed that there was an inexplicable 

 something, a " vital substance," which he was unable 

 to fathom, and which later became the basis of Stahl's 

 phlogiston theory. Commenting on this mysterious 

 substance, Boyle says: "The difficulty we find in 

 keeping flame and fire alive, though but for a little 

 time, without air, renders it suspicious that there be 

 dispersed through the rest of the atmosphere some 

 odd substance, either of a solar, astral, or other 

 foreign nature; on account of which the air is so 

 necessary to the substance of flame!" It was this 

 idea that attracted the attention of George Ernst 

 Stahl (1660-1734), a professor of medicine in the 



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