—, mines of Almaden, xxviii, 21.
—, extracts from a journal, on the mining industry of, F. Le Play, xxviii, 17.
—, Madrid, science in, xix, 194.
Spark extinguisher, xlii, 209.f
—, electric, see [Electric.]
Sparks in the freezing of water by ether, Pontus, xxvi, 178.
Sparrows, number of caterpillars taken by, ix, 200.
Spatangus, see [Zoology, Radiata.]
Spathic iron, see [Iron, carbonate of.]
Specific gravity, considered as a mineralogical character, xvi, 260.