Hydroxanthic acid, vii, 376.

Hygrometer, Daniell's, remarks on, E. Loomis, xlvii, 19; xlix, 277.

—, portable, A. A. Hayes, xvii, 351.f

Hygrometric Register at Western Reserve College, E. Loomis, Sept.-Nov. 1838, xxxvi, 166;

–1838-1840, xli, 315;

–1841-44 xlix, 271.

— —, at Hudson, Ohio, compared with those at Greenwich, E. Loomis, xlix, 276.

— observations, mean of, at Malvern, in Worcestershire, xxxviii, 102.

— —, at Matanzas, A. Mallory, xxxi, 287.

— —, at New Orleans, Barton, xxxi, 400.