Stream Pollution
The wastes of our civilization threaten one of its vital resources: pure water. The solution to the problem is the fuller utilization of modern methods of waste treatment
Volume 186, Issue 3
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Features
Mound Builders of the Mississippi
Between the expeditions of De Soto (1541) and Marquette (1673) this thriving culture vanished from the valley. Its history is now being reconstructed, principally by an ingenious statistical method
Smell and Taste
Two of the five senses depend upon chemical stimuli rather than physical. The chemistry of the substances that these senses can detect and differentiate are important clues to their mechanism
The Quantum Theory
Concerning the early years of this fundamental concept of modern physics: how Max Planck formulated it at the turn of the century and how others enlarged it up to 1923
Measuring Starlight by Photocell
The device which transforms light into electricity, used in conjunction with the telescope, has brought a new insight to some central problems of astronomy
Maxwell's Poetry
The great English physicist wrote some amusing light verse. Herewith a small sample of it, written mostly at the expense of the British Association for the Advancement of Science
How Animals Change Color
The chameleon is only one of many creatures that possess special cells for this purpose. Notable among the others: the catfish, the flounder, the tree toad, the squid and man
Logic Machines
The ancient idea of a device which would test the validity of a system of thought has recently made progress. A very simple machine can be made from page 71 of this magazine