AND WHAT THEY ARE MADE FOR. 
91 
ever changed in form in the progress from plant to animal or from one animal to 
another, all the food and all the substance of all animals were made by plants. 
And this is what plants are made for. 
! 282. Notice also that plants furnish us not merely needful sustenance, but almost 
every comfort and convenience. Medicine for restoring, as well as food for support- 
ing health and strength, mainly comes from plants. 
283. They furnish all the clothing of man ; - not only what is made from the 
woolly hairs of certain seeds {cotton) , or from the woody fibres of bark {linen), and 
what is spun from Mulberry-leaves by the grubs of certain moths (as silk), but 
also the skin and the fur or wool of animals, owe their origin to plants, just as 
their flesh does. 
284. They furnish utensils, tools, and building materials, in great variety ; and 
even the materials which the mineral kingdom yields for man’s service (such as iron) 
are unavailable without vegetables, to supply fuel for working and shaping them. 
285. They supply all the fuel in the world ; and this is one special service of that 
vegetable matter which, in the solid form of wood, does not naturally serve for food. 
Burned in our fire-places, one part of a plant may be used to cook the food fur- 
nished by another part, or to protect us against cold ; or burned under a steam-boiler 
it may grind our corn, or carry us swiftly from place to place. Even the coal dug 
from the bowels of the earth is vegetable matter, the remains of forests and herbage 
which flourished for ages before man existed, and long ago laid up for his present 
use. We may proceed one step farther, and explain where the heat of fuel comes 
from ; for even a child may understand it. Plants make vegetable matter only in 
the light, mostly in the direct light of the sun. With every particle of carbonic 
acid that is decomposed, and vegetable matter that is made, a portion of the sun’s 
heat and light is absorbed and laid up in it. And whenever this vegetable matter 
is decomposed, as in burning it, this heat and light (how much of each, depends upon 
the mode of burning) are given out. 
286. So all our lighting as well as warming, which we do not receive directly 
from the sun, we receive from plants, in which sunlight has been stored up for our 
use. And equally so, whether we burn olive-oil or pine-oil of the present day, or 
candles made from old peat, or coal-gas, or lard, tallow, or wax, — the latter a vege- 
table matter which has been somewhat changed by animals. And, finally, 
287. The natural warmth of the bodies of animals comes from the food they 
eat , and so is supplied by plants, A healthy animal, no longer growing, receives into 
