FO 
-dark and fhade, a oxygen, and, in the funfhine, the carbon, 
e fame time ‘he oxygen alone, and keep 
itfe If as no ourifhment ; as all thefe difecat 
operatio ons have one general effeét, viz. the decompofing the 
air in contaé with plants, it feems more than probable that 
vegetables derive their principal food from this decompo- 
trary to 
th a el a air itfelf, or an air approac aching to its nature, 
maintains a plant remarkably well in its full = ur, and 
‘that carbonic acid gas coucentrated, or without a a 
portion of refpirable air, kills alfo plants, as “this air a 
all other airs, poifonous to i aie lifes are alfo deltrudtive 
of animal life ; woes do sis writer offered firft, in 
gontradi€tion to = of th o celebrated philofophers 
. In geshou fhould, however, have 
eriments, in oppofition to 
the firit has, 
= 
he aflures us, fed plants with hydrogen or inflammable air, — 
till they became, comparatively {pea ings ae among 
piel How then, he afks, does it act a ifon? If 
Sale it m oft Gace food 
t 
the a that the plants abforb this oo air and turn 
it into their nourifhment, the of chemilftr 
was not publifhed ; and, being _ Sighee nt of all the beauties 
of that fyftem , he- was una reduce thefe faéts to a 
pofed of oxygen deprived of its ca 
and of carbon, it is not difficult to anderltand (oe plants 
own nouri y producing 
this nourifhment, which is when they are in the n 
really pa vee as all plants eon * with 
e ace ce than in the light, as 
M. Du Ha net, ts Geneva, found. Plants 
in general grow lefs, it is fuppoted, towards the middle of 
the day than at any other time; many do not advance at all 
when the fun is near the meridian ; ; pe even become ma- 
nife y fhorter towards that time of the day. 
writer has alfo arate ae the ses of plan ts, 
even ae expofed to the funfhin carbonic acid 
gas, but that the leaves aud green ails ie this acid 
only in the dark ; and that flowers and fruits, with a few 
exceptions among the laft, produce at all times, even oe 
roots, carbonic acid. ‘Thus there is no time loft, fom 
or see whole plant, being conftantly seated in this is sais 
of preparing carbonic acid. ‘hough M. Haflenfratzfeems 
ra believe that plants do pa t derive the carbon aes his opinion 
their true nounthment) om the carbonic acid, but find 
‘ready made in the dung; ae doctor, however, serie it more 
probable that plants ae it = from the carbonic ac, 
O D. 
which is a fubftance very eafily een Tie into its twa 
ingredients, VIZ. OX d carbon. ] manures, os 
how a 
rbor [ a 
new 2 fas oe. riz of it, and, accordin 
none at all. Though, according to thefe principles, it could 
ot be accounted for theoretically, it is thought we have 
e hand fa&s enough, from which it feems evident, that the 
nmon air can by itfelf furnifh all the eee for the 
compofition of carbonic acid, as we aaa fee bye and bye. 
t is fuggefted, that we are as eae rom, under- 
ftanding pad various (saa cara dhich ir in ee world are ex- 
pofed to our fenfes as offsprings trom the infinite combina- 
tions, decompo oitons, chemical affinities or attra€iious, &c. 
every where in a€tion, on the furface, and in the bowels of 
ropagat s and vegeta 
writer ie ina fron 
at all. 
ieee acid. Calcareous ftones and alkaline falts, deprived 
of their carbonic acid by fire, regain it folely by the expo- 
fure to the open air. If this produétion c 
fuch fimple means, can we be a 
raw it 
the fubftances which enter into 
een many others o 
- is further remarked that M 
bran 
t forth v new buds, flowers,, an 
protic: rit olor all the ape ‘branches remaining e 
ed to the open air, fhew no fignso ife ; being, with their 
ong as he root 
u 
rive from the furroundiag : air alone all it w 
form _ the eee receflary 10 its growth and pro- 
pagation. By watching all its phenomena, - “will be 
found cn the air in contaét’ with it, but in a 
very different way by day and 
forms thefe tranfmutations of air chief 
— to per- 
its ara 
met it was draw 
= 
Oo So 
Me pay 
= 
er 
and evaporate fro am 
double phenemenon being con os ually eae ed in all parts 
of living animals, the difficulty si aes | it vanifhes 
of 
