2. 



Hf 



thel 



and 



"otti 



a 





;ra 



o\v ; 



IS 



gree of 



ithl 



IS ac 



fiofls 



sat 



I me as in 



leath th 

 3 ; that i 



e 



13 



T heat of 

 le winter 

 '.v to find 



only fuf- 

 cr winters 



mil- 



ome 



old, both 



jc 



h air in 



> 



or 



fheep 



abforbed 

 creatures 



enlarges^ 



m babita- 



tra 



vellers 

 .ith 6°^^ 





io 



tjotH 



Sect. XIIT. 2. 



3- 



ELECTRICITY. 



3^9 



both of them a redundancy of oxygen compared 



th 



water 



hich they may have acquired in their defcent through the atmo 



fphere ; and that as oxygen is fliewn by the experiments 



of Ing 



d Senebier to promote the growth of feeds and of plants, he 



d fnovv promote vegetation in a much 



concludes, that 1 

 greater dcsfi'ee th 



w 



hich feems to accord with 



the popular obfervations on this fubje6l. 



3. Mr. John Hunter by applying thermometers to the internal parts 

 of vegetables newly opened difcovered, that they poflefled in froRy 

 feafoifs a degree of heat above that of the atmofphere, though lefs 

 than that of'^cold blooded animals. Whence another deleterious efFea 

 of cold on vegetable bodies muft be by deftroying their irritability. 



by that means floppin 



th 



e 



bforpt 



d 



of th 



juices ; in the fame manner as is feen in the pale benumbed fingers of 

 fome people, when expofed to the cold ; and which is the immediate 



feof d 



th 



wh 



o 



perifh 



the fnow in winter, which 



o- before their fluids are frozen 



The necelfity of a certain d 



cr 



of heat to produce or to prefe 



aivity of the abforbent veffels of vegetables is well evinced by 

 the experiments of Hales and Duhamel on the rifing fap of 



the vernal month 



O 



frofty day, when the fun (hone on one 



of thofe wounded trees, the fap flowed on the fouth fide of the t 

 but not on the north fide. Phyhque des arbres, Vol. II. p. 258. 

 Duhamel further obferves, that the maples in Canada, where the froft 



M 



is long and f 



evere, begin to bleed, when wounded with the firfl: 



thaw, and flop again, when it free 

 occurs only on the fouth flde of th( 



and that this in frofty days 



This acquaint 

 fpedt to organ 



that one of the principal properties of heat 



bodies, whether of vegetables 



anim 



con- 



fifts in its ading as a ftimulus ; and that in a greater 

 that, which the organized beingr has been accuftomed 



quantity th 



& 



to, 



adts 



fs of flimulus ; and thus increafes the a(5tivity of the fyflem 



in 



