Feature

Shade of Trees Measures “Ripeness” of Timber

Research Needs Freedom, Says National Academy Head

Persistent Hoarseness Is Early Sign of Cancer

First Glances at New Books

Front Matter

Stars and Comets Affected by Cosmic Radiation

Smallpox Is Unnecessary but Still on the Increase

Dyeing Studies Give Size Index of Cotton “Pores”

Stone Age Secrets Wrested from Old Weapon

Coast of Australia Shaken by Earthquake

Helium Suggested as New Preventive of “The Bends”

Action and Immune Serum Prevent Measles Epidemic