COLOURED LIGHT. io 
of food in the soil in which they were placed. 
Under the green light the plants grew slowly, 
but tolerably strong; yet none would flower, 
notwithstanding the greatest care and attention 
were bestowed upon them. The results under the 
blue glass were very different. The roots germi- 
nated a little less quickly than in the open air; 
but the plants became compact and healthy in 
their character, putting forth their flower-buds 
strongly, and flowering in perfection. Under this 
light alone did the various processes go on with 
that vigour which is characteristic of vegetation 
in the open air. 
A very striking circumstance occurred in the 
experiments with the red light. It has been 
already seen that plants turn eagerly toward the 
light; and this fact may often be witnessed in 
our sitting-rooms where a plant is placed in a 
window, for in a few weeks it is seen to have 
bent itself, as if in grateful homage, to the light 
of day pouring in at the window. Very opposite 
to this was the behaviour of plants, upon whose 
tender structures the fierce red rays were alone 
allowed to fall. As if sensible of their dele- 
terious influence, the plants actually turned away 
