78 THE AIM AND ACHIEVEMENTS OF SCIENTIFIC METHOD. 



29. 



Meanwhile, however, a vastly more powerful intellect than 

 that of Boyle was preparing the atom for a wider career of 

 usefulness. Newton's Principia made it possible for Laplace 

 a hundred years later to present to Napoleon the atomic 

 Weltanschauung in which he had found no need of any such 

 hypothesis as that of a Creator. In an admirable chapter 

 on " The Astronomical View of Nature," Dr. Merz has drawn 

 a most lively and interesting picture of the way in which 

 Newton's astronomical views " spread into molar and molecular 

 physics," and has traced this enormously fertile stream of 

 investigation arid discovery to its sources in the notion of 

 attraction (to which for the first time Newton gave a quanti- 

 tative meaning), and in Newton's own suggestion made in the 

 famous "Query 31 " with which the "Optics" closes, that the 

 behaviour of material substances might in a multitude of cases 

 be interpreted by means of the notion of attractive or repulsive 

 forces acting between the hard, solid particles of which they 

 might be supposed in ultimate analysis to consist. 



30. 



But it was not until ten years ago, when the twelve 

 volumes of John Dalton's lecture and laboratory notes were 

 discovered in the rooms of the Literary and Philosophical 

 Society of Manchester, where his experimental work was 

 carried out,* that it became more than a shrewd biographer's 

 surmise that the father of modern chemical theory had drawn 

 his inspiration from the same source. At the conclusion of 

 the notes on a course of twenty lectures delivered at the Eoyal 

 Institution^ during the winter of 1809-10, Dalton copied 



* Eoscoe and Harden, JNew View of Dalton's Atomic Theory,- 1896, 

 p. 12. 



t P. 125. 



