6 
NATURAL CONDITIONS OF PLANTS. 
LIGHT. 
“ Even as the soil which April’s gentle showers 
Have filled with sweetness, and enriched with flowers, 
Rears up her suckling plants, still shooting forth 
The tender blossoms of her timely birth; 
But if denied the beams of cheerly May, 
They hang their withered heads and fade away.” 
It is hardly possible to overrate the influence 
of light upon plants. Its intensity, however, 
varies exceedingly. Sir J. "W. Herschel says 
that the light at the Cape of Good Hope, when 
compared with that of our brightest summer’s 
day in England, is as 44° to 27°. In other 
situations, plants are found growing where the 
light is not more than half of what would be 
given by an ordinary candle. Very much of 
our success in horticulture depends upon the 
proper amount of light ; and, the fact that flower- 
ing plants generally require more light than 
ferns, is one principal reason why the former do 
not succeed so well in closed cases in rooms, as 
the latter. A plant of Linaria Cymballaria lived 
for some years in a closed case on the top of 
a model of a portion of Tintern Abbey. The 
branches which grew towards the light, invari- 
ably produced leaves of the full size, with per- 
fect flowers and fruit, whilst those branches 
