168 FRAGMENTS OF SCIENCE 



the body, and that of the coal in the furnace. He would 

 assuredly have anticipated Mayer in calling the blood 

 which the heart diffuses "the oil of the lamp of life, 11 

 deducing all animal motions from the combustion of this 

 oil, as the motions of a steam-engine are deduced from 

 the combustion of its coal. As the matter stands, how- 

 ever, and considering the circumstances of the time, the 

 boldness, clearness, and precision, with which Descartes 

 grasped the problem of vital dynamics constitute a mar- 

 vellous illustration of intellectual power. 1 



During the Middle Ages the doctrine of atoms had 

 to all appearance vanished from discussion. It probably 

 held its ground among sober-minded and thoughtful men, 

 though neither the church nor the world was prepared to 

 hear of it with tolerance. Once, in the year 1348, it re- 

 ceived distinct expression. But retractation by compulsion 

 immediately followed; and, thus discouraged, it slumbered 

 till the seventeenth century, when it was revived by a con- 

 temporary and friend of Hobbes of Malmesbury, the or- 

 thodox Catholic provost of Digne, Gassendi. But, before 

 stating his relation to the Epicurean doctrine, it will be 

 well to say a few words on the effect, as regards science, 

 of the general introduction of monotheism among Euro- 

 pean nations. 



"Were men,'* says Hume, "led into the apprehension 

 of invisible intelligent power by contemplation of the 

 works of Nature, they could never possibly entertain any 

 conception but of one single Being, who bestowed exist- 

 ence and order on this vast machine, and adjusted all its 



1 See Huxley's admirable "Essay on Descartes." "Lay Sermons," pp. 

 364, 365. 



