Mr. Thornton requested that Percy remain for lunch in order that they
might return to the field to let him see the soil acidity tests made.






CHAPTER XIII

WHY PERCY WENT TO COLLEGE





"I AM interested to know where you learned these things about acid
soils and lime and limestone," said Mr. Thornton.

"Mostly in the agricultural college," replied Percy, "but much of
the information really comes from the investigations that are
conducted by the experiment stations. For example, the best
information the world affords concerning the comparative value of
burned lime and ground limestone is furnished by the Pennsylvania
Agricultural Experiment Station. Those experiments have been carried
on continuously since 1882, and the results of twenty years' careful
investigations have recently been published. A four-year rotation of
crops was practiced, including corn, oats, wheat, and hay, the hay
being clover and timothy mixed. With every crop the limestone has