| Es haope. J 
which was flopt during the darknefs . 
of the night; that this. operation of 
the plants 1s more.or lefs brifk in pro-~ 
portion. to the clearne/s of the day, 
and the expofition of the plants. more 
or lefs adapted to receive the ‘direct 
influence of that. great luminary ; 
that plants fbaded by high buildings, 
or growing under a dark fbade of 
other. plants, do not perform. this 
office, but, on the contrary, throw 
out an air hurtful to animals, and 
even eee ge air Bet of ¥ a ‘i= 
eT dingies towal 6 the chafe ae, 
the day, and ceases entirely at fun-fet, 
except in a few plants, which continue 
this duty fomewbat longer than others; 
that: this office is not performed by 
the. whole plant, but only by the. 
leaves and the green falks that fup- 
pe: them 3. ee Ae —— 
