THE ATOMIC VIEW OF NATURE. 395 



many chemists previous to Dalton had to be interpreted 

 as referring not only to such quantities as the balance 

 could determine, but to the very smallest immeasurable 

 particles of which chemical substances consist. For 

 this purpose Dalton adopted what was known as the 

 atomic view of matter. The conception of matter as 

 made up of independent particles, which for our means 

 and methods prove not only indestructible but likewise 

 indivisible, was revived as the ancient theory of attraction 

 had been. Combined with the Newtonian view that 

 weight is a universal property of all matter, it made the 

 two fundamental rules of chemical action intelligible : 

 the two facts first, that the total weight of substances 

 remains always the same, be they combined in ever so 

 many different ways ; and secondly, that all substances, 

 be they in large or in small quantities, combine with each 

 other, or separate from each other, in definite and fixed 

 proportions. This view could not be consistently main- 

 tained, except it was referred to the smallest particles 

 into which matter is practically divisible : the figures 

 expressing the combining numbers were viewed by Dalton 

 as representing the relative weights of the actual atoms 

 or elements of matter. That the ultimate particles of 

 matter have definite weights is the reason why substances 

 combine in fixed proportions, and why the combining 

 weight of the compound is the sum of the combining 

 weights of the constituents. 



As the gravitation formula had given rise to a sur- 

 prising activity in physical astronomy, to a long series 

 of exact measurements, and to theoretical deductions of a 

 purely mathematical kind, so the atomic theory of Dalton 



