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containing in them Oill fmaller veilels ; in thefe veni-ls I have feen the 

 juices (at the time the Wheat ftalks are growing) running with a 

 wonderfully rapid courfe ; and, through the joints or valves in thoie 

 veflels marked G, the juice was carried upwards, which juice was for 

 the greateft part compofed of globules ; and when thefe globules 

 came to pafs the valves where the paflage through the veflels is very 

 narrow, they aflumed an oblong figure, until they came into a 

 larger fpace, when they reaflumed their priftine globular fliape. 



Fig. lo reprelents thefe afcending veflels cut longitudinally, and 

 feen through the microfcope, being the fame which in fg. 9, are 

 marked GG ; at IiII, are the valves I have mentioned, and, in tliofe 

 parts, the paflages through the veflels are the moft narrow or con- 

 fined of all. 



The flalks of Wheat, are formed of none other than perpendicular 

 or afcending veflels, and that, in my judgment, is the reafon, why 

 they are furnifhed with a kind of joints or knots, at certain intervals, 

 in order to give ftrength to them ; and that, without fuch joints, the 

 flalk would not be able to fupport the ear, which is its fruit. This is 

 alfo the cafe with grafles, and likewife with reeds, for the lame rea- 

 fon ; and it alfo obtains in the bodies of fome trees. In thefe northern 

 parts, indeed, all trees are provided with horizontal veflels, whereby 

 they have a fufficient ftrength ; but, in the warmer climates, where 

 many of the trees have no other than perpendicular veflels, fuch as is 

 the cocoa-nut tree, the want of horizontal veflels is compenfated, by 

 numbers of thefe kind of joints, formed at fhort intervals, through 

 the whole length of the tree. 



The farinaceous or mealy part, of which the grains of Wheat are 

 principally compofed, confifts of thofe minute globules I have before 

 noticed. Thefe globules are, fmgly, tranfparent, and lie clofely 

 compa6led within a kind of membranes, fo exquifitely thin and tranf- 



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