An authority on precious stones, and especially the diamond, he succeeded in artificially making some minute specimens of the latter gem; and on the discovery of radium he was one of the first to take up the study of its properties, in particular inventing the spinthariscope, an instrument in which
inventing הגייה עם משמעויות, מילים נרדפות, הפכים, תרגומים, משפטים ועוד