“You do not mean that we’ll have to remember and answer questions just like school?  You surely do not mean that, Big Chief,” broke in Albert.

“No,” replied the man laughing, “no, you may forget it all if you like.  Remember it, if it seems to you useful.  But if it’s a strain on you, Albert, make it your business to forget.”

They all laughed at this, but none so heartily as Albert himself.  “That’s one on this old head of mine,” he said, banging that member up against the side of the chimney.

“My first talk I have given you in part, but I have more I wish to add.  I believe even Albert can stand it.  The subject is the soil.

“Soil primarily had its beginning from rock together with animal and vegetable decay, if you can imagine long stretches or periods of time when great rock masses were crumbling and breaking up.  Heat, water action, and friction were largely responsible for this.  By friction here is meant the rubbing and grinding of rock mass against rock mass.  Think of the huge rocks, a perfect chaos of them, bumping, scraping, settling against one another.  What would be the result?  Well, I am sure you all could work that out.  This is what happened:  bits of rock were worn off, a great deal of heat was produced, pieces of rock were pressed together to form new rock masses, some portions becoming dissolved in water.  Why, I myself, almost feel the stress and strain of it all.  Can you?

“Then, too, there were great changes in temperature.  First everything was heated to a high temperature, then gradually became cool.  Just think of the cracking, the crumbling, the upheavals, that such changes must have caused!  You know some of the effects in winter of sudden freezes and thaws.  But the little examples of bursting water pipes and broken pitchers are as nothing to what was happening in the world during those days.  The water and the gases in the atmosphere helped along this crumbling work.

“From all this action of rubbing, which action we call mechanical, it is easy enough to understand how sand was formed.  This represents one of the great divisions of soil—­sandy soil.  The sea shores are great masses of pure sand.  If soil were nothing but broken rock masses then indeed it would be very poor and unproductive.  But the early forms of animal and vegetable life decaying became a part of the rock mass and a better soil resulted.  So the soils we speak of as sandy soils have mixed with the sand other matter, sometimes clay, sometimes vegetable matter or humus, and often animal waste.

[Illustration:  Constant Cultivation of the Soil Saved George’s Cabbages

Photograph by Karl W. Helmer]