very different from what it is now, for the seas flowed over vast areas which are now solid ground.  Immense trees grew in those times, and the great ferns and palms and tropical plants grew in portions where now they cannot grow because it is too cold.  I want to draw some trees and bushes to represent this great growth. [Draw trees and bushes of Fig. 72 in green.] And also the bright warm sun which, together with the abundance of water, caused them to grow so profusely. [Draw the sun in orange, completing Fig. 72.] Then, the geologists tell us, there came a great change.  There were awful volcanic disturbances which caused the sea to overflow great areas of these trees and bushes and ferns, and they were buried from sight by a vast expanse of water.  Gradually, though, another change came.  The waters receded into lesser areas and the ground arose from beneath the waves.  But the trees and the bushes and the ferns were gone.  Where?  They had been buried deep beneath the mud and sand and stones which the waters had washed over them.  Then, after that, God created the monster mastodon and the mammoth and many other beasts which have since disappeared from the earth, and finally man was created to have dominion over the earth.  For many centuries afterward, no one knew that the earth was once the place of immense trees and ferns and rank vegetable growth which had since been buried beneath the surface.  But one day, some of this old, buried vegetable matter was found and brought to the surface of the earth.  By that time it was not green any longer.  It was hard and compact and looked very much like black stone.  Someone seemed to think it would burn if fire were applied to it.  And, strange to say, it did burn.

[Illustration:  Fig. 72]

“Thus was coal discovered.

“Ever since then, we have been digging from the depths of the earth the coal which was deposited there in those ages of the past.  And it is blessing the world everywhere. [With the broad side of your black crayon, quickly cover the vegetation of Fig. 72.  Then, with broad strokes of the orange chalk, or with a combination of the yellow and the red, draw the flames, completely covering the sun, and finishing Fig. 73.] Coal is now the chief of the elements which bring warmth to our homes, our places of business and everywhere that we are spending our time indoors; it is the great factor in our great manufacturing and transportation enterprises.  God laid it all up for us millions of years ago!

[Illustration:  Fig. 73]

“Thus do we find a splendid example of what real service is.  Jesus came to the earth to be of service to the world.  When he departed, He left behind Him the command that the gospel should be preached to every creature—­that the light and warmth from His life should not remain buried in us but that we should take that warmth to every portion of the earth, that it might, like the hidden sunshine in the coal, bring life to those in the cold and darkness of heathenism.