Feature

Observations of Sunspot Variation: “A Classic of Science”

Goitres Occur in Epidemics, Mayo Clinic Study Suggests

Pot-Hunters Damage Prehistoric Pacific Port

Girls Learn More by Rote; Understand Less than Boys

Front Matter

Bureau of Standards First in This Country to Liquefy Helium

Stone Age Town Is Found in Delta of the Nile

Discovery of Two New Essentials to Life Reported by Chemists

Panamanian Bug Is Genuine Bugbear

Dogs Get New Type of Training to Serve as Guides for Blind

Reports 21-Year Experiment in Goitre Prevention

All Flyers Began as Gliders