48 ANIMALCULA OF INFUSIONS. % 



, that the germs of animalcula of a fimilar con- 

 ilitution may exift. In confirmation of all this, 



I may 



eft degree of heat in the fliade that I have )'et met with 

 %vell authenticated. 



Although the direa: rays of the fun are not fo powerful 

 as the author fuppofes, the heat which various fubftances, 

 from their peculiar nature, receive from them, is great- 

 er than can eafily be imagined : and there may adlually 

 be countries where the heat of certain fpots does equal 

 that of boiling v.'ater. We read of the fand fo hot that 

 the feet can hardly be borne upon it- In Senegal, it was 

 168° ; and Adanfon fuppofes, that the thermometer might 

 have rofe higher had the tube admitted ; and eggs har- 

 dened in it, Hift. Natur. p. 131. At Marfeilles, it is faid^ 

 Dr Raymond found the earth heated to 170^, Kirnuan on 

 differejzt Te7?ip£ratiires,from Mem. de la Societ. Med. de Parisy 

 1-78. But it depends entirely on the fubftance what heat 

 it will receive. The fand of Goree, which confifts of bro- 

 ien fhells, was heated only to 113^, Prelong, Memoir e ; and 

 we have feen that the thermometer in the fhade rifes al- 

 inoft as high. 



Some perfons have imagined, I know, that if the heat 

 was as "-reat as the author admits, all the rivers would boil. 

 This by no means follows, for one fubftance is not only 

 more eafily heated than another, but will receive more and 

 retain it lo.ieer ; and at Marfeilles where the earth was 

 heated to 170*, the fea was only 45*^. The like has been 

 found in other inftances, and is dally evinced in water in 

 particular. 



From all thefe fads, we are wan-anted to conclude that 

 there may be places in the world, where in particular 

 fituations, and aided by collateral circumftances, fome ani- 

 nial eggs or vegetable feeds may be expofed to heat not 



inferior 



