112 
CONTENT. 
elaborated. Vegetables fashion elementary or mine- 
ral matter ; and when fashioned those matters pass 
ready formed into the bodies of animals ; — animals 
change one portion of them, and store up another in 
their tissues : — they engender heat, and elicit force 
in consuming that which vegetables have produced and 
slowly accumulated. This is the relation between 
the luminous insect, and the soil charged with phos- 
phates. What the plant reduces, the insect appro- 
priates and consumes ; — plants decompose carbonic 
acid to seize upon its carbon, and they decompose 
water to seize upon its hydrogen ; animals burn car- 
bon to form carbonic acid, and they act on hydrogen 
to form water. The Fire-fly, in its economy of life, 
burns the phosphorus, absorbed from the plants that 
nourished it, to give forth light. The phosphorus in 
a state of combustion unites with the oxygen of the 
air, and when we experimentalise this process of com- 
bustion, in order to trace the parts severally played 
by vegetables and by animals in the economy of 
nature, we find that phosphorus, when it unites with 
the oxygen of the air, produces a solid acid, which 
falls down in the included air like flakes of snow, and 
in this way it again combines with the soil. 
It is certain that the Fire-fly feeds upon the 
sugar-cane ; and should the larva do so likewise, as it 
is xylophagous, this insect must be added to those 
that do mischief to the planter ; considering the 
abundant swarms which nightly, at certain seasons, 
illuminate the cane-flelds. When Mr. Lees, from 
the Bahamas, carried the living Fire-fly to England, 
he took sugar-canes to sea with him, on which the 
