20 Anatomy of the Vine. 



berry, owing to their cellular and horizontal vessels, as well as 

 their liber containing an abundance of gallic acid, which would 

 cause the precipitates, as before mentioned, to blend together. 



Some of the ascending sap-vessels of the vine are remark- 

 ably large : an individual one might be traced from near the 

 point of a root to within a short distance of the claw, as I shall 

 term it (for the six together resemble the claws of a bird, and 

 the idea is strengthened by the stalk of the leaf resembling its 

 lea 1 ) ; see Jig. 2. at efg h i k, which represent the six claws, 

 and the stalk or leg at m. These vessels become much smaller 

 near the claw ; and, on entering it, they are extremely fine, so 

 that the finest hair cannot be passed down them, but which 

 might have been easily done to any other except those six. 



On looking at the alburnum, one would suppose the ascend- 

 ing sap-vessels in drawing^. 4., from q to r, marked k h, and 

 in Jig. 3., b c de, were formed merely by leaving small circular 

 holes during its growth; but on minutely examining them 

 with a powerful microscope, it will be discovered that each 

 hole contains a vessel within, of a remarkably fine, silvery, 

 paper-like texture, which possesses the power of protruding 

 the sap forward, as will be more fully illustrated hereafter. 



I am well aware of the interesting theory of the vital mo- 

 tion, &c. &c, by Monsieur Dutrochet, mentioned in Vol. III. 

 p. 78., and more fully in No. I. of The Foreign Quarterly Re- 

 view, p. 78. ; but I consider that every vegetable action arises 

 from a vital principle, inherent in itself, and not from the at- 

 traction of heavy fluids, even when confined in a membrane 

 or sac, for others of lighter specific gravities, which that gentle- 

 man calls endosmose ; and exosmose when lighter fluids pass 

 outwards through such membrane or sac into heavy fluids ; but 

 that this vessel, or lining of the alburnum, possesses an animated 

 power to protrude the sap forward. The following experi- 

 ment will more clearly exemplify my meaning : — Cut off an 

 inch or two from the middle of a collet of a vine, and, after 

 making both ends very smooth with a sharp clean knife, 

 moisten the upper end a very little with the solution of the 

 sulphate of iron ; afterwards, put a few drops of the prussiate 

 of potash on the concave side of a watch-glass, and then place 

 therein the other end of the collet ; in a few minutes the upper 

 end will become spotted with blue, from the prussiate of potash 

 having ascended up those vessels and precipitated the sulphate 

 of iron on the upper surface. Now, as no leaves, joints, or 

 roots of the vine were attached to the collet, nothing but its 

 own vital principle could have raised the solution. Some may 

 think the union of the divisions by lateral pressure might pro- 

 duce the ascent : this is easily proved to be incorrect ; for, on 



