440 On the different Sorts of Lime ufed in Agriculture. 



natives of tlie Torrid Zone, that yield a milky juice, pofTefling qualities nearly of the 

 fame nature, as artocarpus integrifolia (common jack tree) ficus religiofus ct Indica, 

 Hippomane biglandulofa, Cecropia peltata, &c. 



The caout-chouc or ficus religiofa, the Hindus confidcr the moll tenacious vegetable 

 juice they are acquaiilted with ; from it their befl bird lime is prepared. I have exa- 

 mined its qualities as well as tliofe of ficus Indica and artocarpus integrifolia, by experi- 

 ments, fimMar to thofe above related, and found them tfiflingly elaftic when compared 

 •with the American and Urceola caout-choucs, but infinitely more vifcid than either!; 

 they are alfo inflammable, though in a lefs degree, and fhew nearly the fame phenomena, 

 •Kvhen immerfed in the mineral acids, folution of ■cauflic alkali, alkohol, fat, and eflcntial 

 oils; but the folution in Cajeput oil could not he feparated, by fpirits of wine and 

 collefted again like the folutions of the Urceola and American caout-chouc. 



IV-. 



'On the different Sorts of Lime vfed in Agriculture, By Smithson TennanT, 



E/q. F.R.S* 



I 



^WAS informed kft fiiftitnev that in the neighbourhood of Doncafler two kinds of 

 time were employed in agriculture, which were fuppofed to differ materially in their 

 effefls. One of thefe, which was procured near the town, it was neceflary to ufc 

 fparingly, and to fpread very evenly over the land ; for it was faid that a large propor- 

 tion of it, inftead of increafing, diminiflied the fertility of the foil ; and that wherever 

 & heap of it was left in one fpbt all vegetation was prevented for many years. The 

 other fort of lime which was obtained from a village near Ferry Bridge, though confi- 

 derably dearer from the diftant carriage, was more frequently employed on account oi 

 its fuperior utility. A large quantity Was never found to be injurious ; and tire fpots 

 which were entirely Covered with it, inftead of being rejidered barren, became re- 

 markably fertile. The different properties afcribed to thefe t^vo kinds of lime wcrc fo 

 very diftintt that it feemed probable they could not be imaginary ; and it therefore ap- 

 peared to be worth the trouble of afcertaintng them more fully, and of attempting k> 

 difcover the nature of the ingredients from Whence the diffewnae arofe. For this plur- 

 pofc I procured fome pieces of each fort of lime-ftone, arid firft tried what would be 

 their effefl upon Vegetables in their natural ftate, by reducing them to coarfe powder, 

 and fowing in them the'fceds of different plants. In both kinds the feeds grew equally 

 Well, and nearly ia the fame manner as they would in fand or any other fubftance which 



* Philof. Tfanfaflions, 1799. jPart 11. p. 30^";. 



affords 



