78 Chemical Philosophy. 



on light, heat, air, water, and other subjects al- 

 lied to those, were in several respects useful, and 

 prepared the way for subsequent improvements. 

 To his learned labours succeeded those of Dr. 

 Mayow, who not only prosecuted the inquiries 

 commenced by Boyle, but had also the honour of 

 devising others, equally new and important. He 

 went far in discovering some of the properties of 

 that portion of the atmosphere which has been since 

 called vital air and oxygen, and ascertained the 

 necessity of its presence for the purposes of com- 

 bustion and respiration.' The discoveries and the 

 works of this experimental philosopher, however, 

 notwithstanding their curious and valuable nature, 

 strangely fell into forgetfulness, and a century after 

 their publication were scarcely at all known among 

 the learned of Europe. In the list of luminaries in 

 chemical science, the immortal Newton next ap- 

 pears. Though his mind was chiefly occupied in 

 exploring other regions of philosophy, he w^as by 

 no means regardless of this; and about the be- 

 ginning of the eighteenth century he first sug- 

 gested the idea of arranging the phenomena of che- 

 mistry under the head of a peculiar species of at- 

 traction. The chemists who lived before this great 

 philosopher supposed that all solvents, or sub- 

 stances capable of dissolving others, were com- 

 posed of particles which had the form of w^edges 

 or hooks; that solution consisted in the insinuation 

 of these wedges or hooks, between the particles 

 of the bodies to be dissolved; and that chemical 

 combination was merely the linking of the diifFer- 

 ent particles together, by means of holes in one 

 set of them, into which the hooks or the wedges of 

 the other set were thrust. Such explanations, ab- 

 surd as they may appear, were generally fashiona- 



l ^ractatus ^ulnqui Medic o-Physlclj p. I a and I06. 



