34^ Of Vegetation. 



a very confiderable influence in expanding 

 the fap in all its parts. The warmth was 

 much greater on the body above-ground, than 

 on the roots which were two feet deep ; thofe 

 roots, and parts of roots, which are deepeft, 

 as they feel much lefs of the fun's warmth, 

 fo are they not fo foon, nor fo much affedled 

 by the alternacies of day and night, warm 

 and cold : but that part of Vegetables which 

 is above-ground, mull have its fap con fid er- 

 ably rarefied, when the heat increafed from 

 morning to two o' clock afternoon, fo much 

 as to raife the fpirit in the ift Thermometer 

 from 21 to 48 degrees above the freezing 

 point. 



When in the coldeft days of the winter 

 1724, the froft was fo intenfe as to freeze the 

 furface of ftagnant water near an inch thick, 

 then the fpirit in the Thermometer , which was 

 expofed to the open air, was fallen four de- 

 grees below the freezing point; the fpirit of 

 that whofe ball was two inches under-ground, 

 was four degrees above the freezing point; 

 the 3d, 4th and 5th "Thermometers were pro- 

 portionably fallen lefs and lefs, as they were 

 deeper, to the 6th Thermometer ; which being 

 two feet under-ground, the fpirit was ten 

 degrees above the freezing point. In this 



ftate 



