Dr. Swammerdam, of Amsterdam, on insects) have il- 

 lustrated to a surprising degree the subjects on which 

 they wrote. 



14. Many hare diligently searched into the nature 

 of plants; particularly Mr. Hay, who has not only 

 ranged them in a new method, but also wrote an ela- 

 borate history of them. Others have described, with 

 equal diligence, either plants in general or those of a 

 particular country ; and others have shewn the like 

 industry in finding out and explaining the nature of 

 stones, metals, minerals, and other fossils. 



15. Nor is it straijgt* that the moderns have pene- 

 trated farther into the recesses of nature than the an- 

 cients, considering the advantages they have received 

 from the art of chymistry. Not that this is an inveiu 

 tion of later ages : it was in some measure known long 

 ago. But as this art has been cultivated in our age, 

 with far greater accuracy than ever, so by this means 

 many properties of natural bodies have been discover- 

 ed, of fossils in particular. 



16. But none of these have so much engaged the 

 study of the learned, or so well deserved it, as the 

 load-stone. Its attractive force was known to the 

 ancients, and the origin of that discovery is recorded 

 by Pliny. But it does not appear that tiiey knew of 

 iis pointing to the pole, or of the use of the compass. 

 This (the compass) was invented by John Goia, in 

 the year 1300: but it has since been observed, that 

 the magnetic needle seldom points exactly to the pole, 

 but varies from it some degrees to the East or West in 

 a fixed and regular order. 



17. Nearly related to the nature of fossils is glass $ 

 which was well known to the ancients, being men. 

 tioned by Plutarch and Lucian among the Greeks, by 

 Lucretius, Pliny, and others, among the Latins. Yet 

 the art of making glass has been since their times 

 abundantly improved. One branch ot this is, the art 

 of making burning-glasses, which are now brought to 

 so great perfection, as either to melt or reduce to ashes 

 the most solid bodies in a few moments. If these svcro 



