A HISTORY OF SCIENCE 



was no satisfactory substitute for this theory, which, 

 even if unsatisfactory, seemed better than anything 

 that had gone before or could be suggested. 



But the good effects of the era of experimental re- 

 search, to which the theory of Stahl had given such an 

 impetus, were showing in the attitude of the experi- 

 menters. The works of some of the older writers, 

 such as Boyle and Hooke, were again sought out in 

 their dusty corners and consulted, and their surmises 

 as to the possible mixture of various gases in the 

 air were more carefully considered. Still the phlogiston 

 theory was firmly grounded in the minds of the 

 philosophers, who can hardly be censured for ad- 

 hering to it, at least until some satisfactory substi- 

 tute was offered. The foundation for such a theory 

 was finally laid, as we shall see presently, by the 

 work of Black, Priestley, Cavendish, and Lavoisier, 

 in the eighteenth century, but the phlogiston theory 

 cannot be said to have finally succumbed until the 

 opening years of the nineteenth century. 



