precipitate was filtered out, dissolved and washed through the filter paper with dilute acid, reprecipitated from a smaller volume, centrifuged, plated and counted. (3) Calcium and strontium were precipitated from the alkaline filtrate by addition of saturated ammonium oxalate solution to the “hot" solution. The preci- pitate was filtered out, dissolved and washed through the paper with acid, reprecipitated from a smaller volume, centrifuged, plated, and counted. - 126 -