Oétob. 
ture 
OF GARDENING, 
SC Pi 
Of the Shep of PLANTS. 
HE nightly Change of Pofture in the Leaves 
of the Lotus, defcribed in this Number, is 
one of the many Initances of what is called the 
Sleep of Plants. 
rate Treatife * 
ciples : | 
That the Leaves of certain Plants affume at 
Night a Difpofition different from that of the 
Day, has been long known: Acosta records it 
This I have explained in a fepa- 
at large, on the following Prin- 
of the Tamarind ; ALpinus of that Tree, and of 
the Abrus; Glycine foliis pinnatis conjugatis, pinnis 
ovatis oblongis, obtufis; and from thefe, all who 
followed: Axprnus extends the Obfervation to 
feveral other of the Egyptian Kinds; and Lin- 
N@vus has carried it much farther among the 
European. 
ALPINUS conceived it a Pissfien of Na- 
ture for the Defence of the nobler Parts, the | 
Flowers and Fruit: and he particularly obferves 
of the Tamarind, that its Leaves embrace the 
tender Pods. . 
This Opinion Ray difclaimed, though he al- 
lowed the Fact: but Linnzus has adopted it. 
I think it will appear, upon a ftri&t Examina- 
tion, that the Change itfelf is a natural Effect, 
refulting from the common Properties of Bodies, 
and their Operations upon one another ; and that 
the Author of Nature has in many Inftances, 
made it effectual to that great Purpofe; though 
in others it happens equally, without anfwering 
any fuch End. 
We fee how far the Obfervations of earlier 
Writers carried the Difcovery ; how much farther 
Linn us: and I perfuade myfelf the Reader will 
accompany me with Satisfaction in a more deep 
Refearch. | 
‘Linnavs has deferved greatly of the World 
in this and other Inftances, by tracing Nature’s 
Steps, and recording thofe Obfervations. To 
relate thefe Facts is to give the Hiftory of Na- 
: but there is fomething more within our 
Reach. The human Mind, daring, tho’ weak, 
and inquifitive under all its Limitations, feeks (and 
fometimes not unhappily) their Caufes. 
“There have not been wanting from the Time 
when this Property in Vegetables was firft regard- - 
ed, fome who have fought its Origin; tho’ all 
yet unfuccefsfully. Thofe who fuppofed it the 
Effect of Heat and Cold, might for a long Time 
feem to have judged rightly; but when we find 
the fame Thing happen with equal Regularity in 
. Sleep of Plants explained, a Pamphlet lately publithed. 
i]. 
Stoves, where there is no Change in the Tempe- 
rature of the Air, we are convinced that Opinion 
cannot be juft. 
They were as far from Truth, who fappofed 
the Health or Sicknefs of the Plant of any Con- 
fequence in this Refpeét; nor can I affirm, that 
I have found Nature in all Inftances confirm L1n- 
n@us’s Obfervation, that it is more obvious in 
young Plants than old. 
It will appear from the following Trials, that 
the fleeping and fenfitive Plants are naturally al- 
lied ; that their Motions, tho’ differently brought 
on, are dependent on the fame Principle; that 
many of the Sleepers approach to the Quality of 
the Senfitives; and that all the Senfitives have 
theirs. one | 
This will fhew the Subjects are connected, and 
the following Experiments will prove, that, with 
this Connection, the Principle of their Motion is 
alfo found. | 
If we can clofe the Abrus Leaves at Noon-day, 
own, we know the Principle of their Change of 
Pofition. 
If we can throw down, as well as clofe the 
Leaves of the fenfitive Plant, without a Touch, 
by removing the Power which keeps them erect, 
and expanded, it will be acknowledged the 
Jatene Principle of their Motion is alfo under- 
{tood. 
We always know the Caufe of thofe Effects 
we can ourfelves produce; and Experiments are 
the true Teft of reafoning. 
We fee a great Number of Plants clofé their 
| Leaves at Evening. “The Fact is as obvious as 
it is ftrange: but we know every Effect has its 
Conjecture ; but in the eftablifhed Properties of 
Bodies, and their known Influence in different 
Cafes, upon one another. ed 
The Structure of Plants we may eafily know; 
and of no Part more perfectly than of the Leaves : 
for a good Microfcope fhews their {malleft Fibres. 
Between the two Skins of the Leaf, which are 
Continuations of the outer Rind of the Stalk, 
there run innumerable Fibres of a larger Kind; 
with Clufters of more minute ones, in various 
Forms among them. 
The larger Veffels are of a woody Subftance, hol- 
low, and fmaller all the Way from the Bafe of the 
Leaf: they are collected together in a compact 
Manner 
and open them again at Pleafure, the World will — 
Caufe ; and we are to feck this, not by vague 
