STRIEGAU, an industrial town of Prussia, in the province of Silesia, is situated on a small, tributary of the Weistritz, 30 miles to the south-west of Breslau. In 1880 it contained 11,470 inhabitants, 6928 of whom were Protestants and 4379 Roman Catholics. Their chief occupations are tanning and the manufacture of albums, portfolios, and other articles in leather. Granite is Analysis. - To detect strontium in a salt-solution, we first eliminate the heavy metals by the successive application of sulphuretted hydrogen (and free acid) and of .sulphide of ammonium in the presence of ammonia and sal-aunnomac. From the filtrate carbonate of ammonia (in the heat) precipitates only the barium, strontium, and calcium as carbonates, which are filtered off and washed with hot water. The analysis of the precipitate is difficult; but any strontia in it is easily detected by means of the spectroscope (see SPECTROSCOPY).