49 
minished depth of shade, diminished brightness of 
colour, as well as gradually diminished form of 
known objects, suggest ideas of distance, and afford 
the means by which it is imitated on a uniform 
smooth surface. Light naturally exhilarates, and 
is associated with all our remembrances of active 
enjoyment. Music heard from a lake may ravish 
the ear with sweetness; but the sight of a happy 
party, with the band, in a boat gay with awnings 
and streamers brightly coloured, under a glowing 
sky, on a glassy surface, reflecting the images of 
lawns and cattle, and scattered villas and cabins, 
and woods and mountain coombs and peaks, re- 
doubles the rapture of the harmony. The ideas of 
light and of colour are not to be dissociated. The 
solar brightness is white in its source, and infinite 
in its variety of refractions. But light and colour 
are adapted to produce in sentient beings a count- 
less diversity of sensations beyond that of exhilara- 
tion. They are mysteriously adapted to the excite- 
ment of instincts, peculiar delights, emotions, pas- 
sions, appetites. They possess powers of electric 
excitement, acting primarily upon the nervous sys- 
tem, and secondarily upon the mind: or they ope- 
rate primarily upon the mind, or some analogous 
faculty in animals below the grade of rational; and 
secondarily upon the nerves and organs of healthful 
action. Most organized beings droop, become tor- 
pid, and wither in long continued darkness. Some 
eyes receive gratification in a superior degree from 
one colour, some from another. St. Pierre observes, 
E 
