
The SciencesAugust 1, 1955
The Speed of Light
Methods for measuring this universal constant have become more and more precise. Yet today there is considerable doubt about the true value. It may even have changed in the past 20 years

The Speed of Light
Methods for measuring this universal constant have become more and more precise. Yet today there is considerable doubt about the true value. It may even have changed in the past 20 years

Tree Rings and Sunspots
Concerning the lifework of A. E. Douglass, who applies the regular variation in the growth pattern of conifers to the investigation of solar cycles and human history