HISTORY OF THE ATOMIC THEORY. 1 19 



go over again much of the same theoretical ground traversed 

 before, but frequently with much less philosophical grasp than 

 the ancients, and much less largeness of conception, although 

 they frequently gain by what seems the littleness of their 

 ideas, and the smallness of their aims. They are contented to 

 speculate on an acid, instead of the formation of a world, 

 whilst those who take a wider ground, such as Newton and 

 Boscovich, can only be sSid, as far as our subject is concerned, 

 to reproduce and improve earlier philosophies. 



The tendency from this time is to increase the number of 

 bodies, which, if not at first called elements, are at least 

 treated as such. This is a needful step towards the chemical 

 theory of matter in its present stage. 



Glauber, although a believer in the general transmutability 

 of substances, did much to help forward the notion of distinct 

 elements in his observations on the aflfinity of bodies. He 

 explains the evolution of ammoniacal gas from sal ammoniac 

 by a fixed alkali, showing that he understood well combi- 

 nation and decomposition, the stumbling-block of so many, 

 and the introduction to <lefinite compounds. " But that a 

 spirit is distilled off by the addition of fixed salts ; the reason 

 is that fixed salts are contrary to acid salts, and if they 

 get the upper hand do kill the same, and rob them of their 

 strength, whereby those things which are mixed with them 

 are freed from their bond, and so it falls out here with salt 

 armoniack, that when by addition of a vegetable fixed salt, tho 

 acidity of the salt armoniack is killed ; the salt of urine, which 

 formerly was bound therewith, gets its former freedom and 

 strength, and being sublimed turns into a spirit." * 



Boyle, who attacked alchemy, and may almost be said to 

 have begun modern chemistry, or rather let us say the transi- 

 tion period, seems to have had one of the clearest, most 

 straightforward, and most common-sense methods of viewing 



* Page 40. The Works of the Highly Experienced and Famous Chyroist, 

 John Rudolph Glauber. London, IC39. 



