Our experiment teaches us that seeds will not sprout until they receive enough moisture to soak them through and through.

This also teaches that when we plant seeds we must so prepare the soil for them and so plant them that they will be able to get sufficient moisture to sprout.

=Experiment.=—­Soak some beans, peas or corn, twenty-four hours; carefully dry them with a cloth.  In one half-pint bottle place enough of them to cover the bottom of the bottle two or three seeds deep; mark this bottle A. Fill another bottle two-thirds full of them and mark the bottle B (Fig. 37).  Cork the bottles and let them stand for several days.  Also let some seeds remain soaking in the water.  The few seeds in bottle A will sprout, while, the larger number in bottle B will not sprout, or will produce only very short sprouts.  Why do not the seeds sprout easily in the bottle which is more than half full?

To answer this question try the following experiment: 

=Experiment.=—­Carefully loosen the cork in bottle B (the bottle containing poorly sprouted seeds), light a match, remove the cork from the bottle and introduce the lighted match.  The match will stop burning as soon as it is held in the bottle, because there is no fresh air in the bottle to keep the match burning.  Test bottle A in the same way.  What has become of the fresh air that was in the bottles when the seeds were put in them?  The seeds have taken something from it and have left bad air in its place; they need fresh air to help them sprout, but they have not sprouted so well in bottle B because there was not fresh air enough for so many seeds.  The seeds in the water do not sprout because there is not enough air in the water.  Now try another experiment.

[Illustration:  FIG. 36.  To show that seeds need water for germination.  The beans in bottle A were soaked 2 hours, those in bottle B were soaked 24 hours.  They were then removed from the water and put into dry bottles.]

[Illustration:  FIG. 37.  To show that seeds need air for germination.  The beans in both bottles were soaked 24 hours, and then were put into dry bottles Bottle A contained sufficient air to start the few seeds.  Bottle B had not enough.  The water in the tumbler C did not contain sufficient air for germination.  See experiment, page 72.]

[Illustration:  FIG. 38.  To show that seeds need air for germination.  Corn planted in puddled clay in tumbler A could not get sufficent air for sprouting.  The moist sand in tumbler B admitted sufficient air for germination.]