Rensselaer Semi-Weekly Republican, Volume 36, Number 85, Rensselaer, Jasper County, 17 June 1904 — How Radium May Be Found. [ARTICLE]

How Radium May Be Found.

The United States government is taking steps looking toward developing the radium-producing resources of the country. The chief of the geological survey announces that he W'ould like specimens of radio-active minerals, and for the guidance of those persons who believe that they possess such specimens it says that the simplest means of detecting radio-activity m a suspected substance is by the use of a photographic plate—the more sensitive the better. The plate should not be removed from its inclosing black paper. The specimen to be tested should be laid upon this black paper in a dark room and left there from two to fifteen hours, a small metal object having first been placed between the specimen and the black paper on the plate. Instead of the metal object a few small nails may be arranged so as to form the initial of the owner and left on the paper-covered plate below the specimen. After thus remaining in the dark room the plate should be developed in the usual manner. If the specimen tested has radio-active powers a photograph of the metal objector of the nail-formed initial will be produced on the plate exactly as if the plate had been exposed to the sun's rays. The test should be made, if possible, with from half a pound to a pound of the material.