U.S. Army chemical munitions

In the forensic laboratories of the 1920s, a chemist checking for poison could make a beaker glow with the brilliance of a gemstone.  Color tests, as they were called, derived from the fact that many toxic materials turn a specific hue if exposed to the right mixture of heat, cold, acid and base. The results can be eerily beautiful: the gorgeous blue of cyanide, the crimson of carbon monoxide as it saturates blood, the peacocking green of arsenic.  A  journalist, watching some tests, once compared the lab at the New York City medical examinerâs office to the glitter of Aladdinâs cave. He…