LAWS OF GOD IF FATUEE. 
9 
trees into a grate and ignite them. What happens ? The original 
light and heat they absorbed from the sun, temporarily stored in 
their tissues as chemical force, comes out of them again as light 
and as heat, warming and cheering us in our dwellings and pro¬ 
moting our health and our comfort. The actual material of those 
logs, as material only, is useless to us. What is useful is the heat 
and the light which that material has stored up. The material 
itself is costly to grow, costly to hew, costly to store. We put 
it into our fire-grates, but, as already shown, we cannot truly 
destroy it, we can only convert it into gas which passes out into 
the atmosphere through costly chimneys. Why do we incur, all 
this cost ? To get back from that troublesome and costly material 
its store of invisible and imponderable but indestructible latent 
life-giving forces. As with wood, so with coal. Regarded as mere 
matter, and from the point of view of the user, the coal itself is a 
costly and useless nuisance from the time it enters the cellar to the 
time it escapes from the chimney-top. Rut without it we cannot 
have its associated light and heat; those forces which it borrowed 
from the sun ages ago when it was a growing forest; forces never 
lost, never wasted, never destroyed. The matter of our fuel is 
indestructible, the power or energy or force carried within that 
fuel or food is indestructible also. We can change the form of 
a force, but we cannot destroy it. Thus we can put the fuel with 
its contained force under a boiler of water, and, igniting the fuel, 
can provide for the escape of the material of the fuel by a chimney, 
while we transfer to the water the force which the fuel carried, 
making the water boil, that is, making the particles of the water 
fly asunder with almost irresistible motion and produce steam. 
The force of heat having thus been converted into motion, we, 
throwing aside the steam itself by any convenient means, commu¬ 
nicate its motion to pistons, cranks, and wheels, and so get various 
effects useful to man. Possibly by the aid of wheels and hands 
we change this force of motion into the force of magnetism, or into 
the force of electricity. The latter we can pass along a wire until 
it meets with an obstructing wire, when immediately it is changed 
into the force of light, and we get the so-called incandescent 
electric light. Or we may convey the electric force into water, 
a separation of whose elements resulting, gives us an opportunity, 
through the silent agency of the chemical force, of getting heat 
from the oxy-hydrogen jet, and a conversion of that heat into light 
if we place anything which can be made white hot within the jet. 
Here then is a whole series of transformations of force. First 
noticing it as light and heat, we find it changed into chemical force, 
