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2. The parts of which they are composed are either 

 liquid or solid. The liquid are usually divided into 

 juices and tears. The juice is to the plant what blood 

 is to an animal, and is various in the various kinds of 

 plants. Tears are liquors which are emitted from them, 

 whether they sweat out of them naturally, or are 

 drawn out of them either by art or by the heat of the 

 sun. Some^of these remain liquid, others grow by de- 

 grees into a firm consistence. 



3. Plants consist of three dissimilar solid parts, the 

 Root, the Trunk, and the Branches. In each of these 

 we may observe three similar parts, the Bark, theWood, 

 and the Pith. 



4. To begin with the Trunk. Here we may first 

 observe the Bark, whose surface consists of little blad- 

 ders, which surround the trunk like a ring. These, 

 which are commonly filled with some kind of juice, be- 

 ing removed, there occur various ranks of woody fibres, 

 curiously wrought in a kind of net work, one row 

 above another. The intervals also between those 

 fibres are all filled with little vessels. The use of 

 the bark seems to be, not only like skin, to cover the 

 wood and pith, but also to concoct the nutritive juice, 

 and forward the growth of the plant. And as to the 

 nutrition of the plant, it is probable the juice ascends 

 from the root through the fibres, and is sustained by 

 the unevenness therein, till it is lodged in the vessels. 

 In these the new juice being mixed, with that they 

 contained before, is fermented and rariiied to such a 

 degree, as is needful for its nourishment. 



It has been a common opinion, that trees only live 

 by the ascent of the sap in the bark, or between the 

 bark and the wood ; but this evidently appears to be 

 a vulgar error, from the instance of a large old elm, 

 in Magdalen College Grove, at Oxford, which was 

 quite disbarked all round, at most places two feet, at 

 some four feet from the ground. Notwithstanding 

 this ; it grew and flourished many years, as well as 



