IS CONCERNING SECT. IT. 



- The ROOTS of plants are to keep them fixed in 

 the earth and to draw food from it; which they do 

 (chiefly at leaft) by their ends which have been there- 

 fore called mouths: In general they affect, an horizontal 

 growth, for the benefit of the fun and air, and never 

 defcendabove a certain depth from the fur face. 



By means of the root, nourifnment proceeds -.hrough 

 the pipes and capillary conduits of plants, continually 

 from the earth, and by the action of the fun and air, 

 circulates, rarifies, and diffributes itfelf. Tins juicy 

 food, fwells the little hags, or cells (of which the 

 fubftance of plants is compoiedj and following thfc 

 different modifications thereof, filtrates athwart the 

 parts. For example. That which is molt pure and fine, 

 ierves to nourifli the flowers and fruits; that which is 

 not fupplies the branches, and leaves, and roots; the 

 moft grofs and earthy ferves for the bark ; and the mofl 

 oily is for gum and rofin. Juft the fame as we find it in 

 animals, where the food they receive into the ftomach 

 paries afterwards into the blood, circulates into the yef~ 

 fels, and purfuing its different degrees of attenuation, 

 Ierves to nouriih the different parts of the body. 



The stems or trunks of plants are for the fupport 

 of the head, and to convey juices from the roots up- 

 wards for the leaves, branches, &c. and are compofed 

 (as the roots) of bladders, and various conduits for 

 air, fap, &c. perpendicular, fpiral, and horizontal from 

 the pith to the bark. Thefe veffels may be fomewhat 

 feen with the naked eye, as in llices of the young 

 ftioots of nut, apple tree, and vine, but very evidently 

 by a microfcope. It is obfervable, that fome plants 

 which are weak and pipy have knots at proper dittances 

 to flrengthen them, and others have clafpers to hold 

 them up; while others are robufl enough, in Hem to 

 brave the fury of ateinpeii. 



The leaves of plants are very Tarioufly, but 

 beautifully conftru&ed in their form and fubltance; 

 and if we confider them as attracting nourilhment 



" from 



