175 
relative to the Motion of the Sap in Plants, 
composed of small green globules, or small bodies of an irregu- 
lar form, as if strung together like the beads of a rosary. They 
are distinguished from the sap of globules by their green colour ; 
and they do not mix with them when flowing at the same time 
out of the divided part of a plant into water. 
If the vessel be divided, many of the stripe-globules near the 
cut will separate from the membrane ; those more remote, how- 
ever, will remain attached to it, and preserve their stripe form, 
only their direction will undergo some change in consequence of 
the lost tension, and the stripes will appear bent into various 
curves, outwards or inwards, and in some places unnaturally ap- 
proached to, or removed from each other ; and in this case, the 
motion of the sap-globules, so far as it still continues, (for we 
have already observed, that all the sap does not flow out at 
once;) follows this new unnatural direction, and appears to pro- 
ceed most rapidly in those places where the stripes have acci- 
dentally run thickest together. 
If the membrane of the Vessel be gradually pressed, all these 
stripe-globules may be forced by degrees in a mass out of 
the aperture made by the cut ; and the membrane will then ap- 
pear quite smooth, pure white, and transparent as glass. Vine- 
gar causes these globules to come out singly, or in pairs, or 
several hanging together, like fragments of a chain, and then 
they appear bound to each other by an extremely delicate mem- 
brane. 
Now, as the cause of the constant and regular motion of the 
sap in this plant cannot possibly be ascribed to any of the pow- 
ers hitherto assumed by vegetable physiologists,'^ — the capillary 
attraction, the alternate contraction and dilatation, or the irrita- 
bility of the vessels, because these are evidently quite passive ; 
while, upon the other hand, the symmetrical stripes above de- 
scribed, as composed of small globules, exhibit the most obvious 
influence, not only on the mode; but even on the degree and reality 
of the circulation; Amici conceives himself justified in assuming 
as an hypothesis, that these stripes are to be considered as vol- 
taic piles, and that the motion itself is to be attributed to the 
influence of galvanic agency ; and this hypothesis seems to be 
supported, on the one hand, by the construction of these stripes; 
and on the other, by the known fact, (although perhaps not yet 
