Feature

Comet Discovered in April Increasing in Brightness

Code Difficulty Rated

Arms of Nebulae Are Trailing Star Centers

New Machines and Gadgets

High-Frequency Field Used in Metal Work

First Glances at New Books

Front Matter

New Pregnancy Test

New Gage Aligns Sights of Garands without Firing

Death Rate Is Rising; Pneumonia Worrisome

Unsafe Jobs for Youths

New Sulfa Drug Is Two to Four Times as Potent