"The Unseen Universe," p. 184.

A recent clever writer likens some of these metaphysical speculations to the act of a baby sucking at a nursing bottle. So long as there is any milk in the bottle, the baby sucks with pleasure and profit. Unfortunately the little fellow does not always stop sucking when the supply of milk gives out, but still keeps on sucking empty air, with resulting discomfort and colic. We all need to recognize the limits of the intellectual milk supply, and not keep on trying to solve problems that are in their very nature beyond the limits of the human mind.

* * * * *

WORKS BY THE SAME AUTHOR

The Fundamentals of Geology

Cloth, 270 pages, Illustrated with engravings, charts, and maps $1.25

"I have been intensely interested, ... and I think you prove your points conclusively."--REV. S. BARING-GOULD,