—, fossil, in the chalk of Kent, xli, 205.
Turton, W., notice of the works of, xxxvii, 161.
Tuscany, boracic acid of, xxviii, 143.
—, — — lagoons of, J. Bowring, xxxvii, 270.
Tweedie, A., Practical Medicine of, noticed, xxxix, 398.
Twilight bow, account of, S. F. B. Morse, xxxviii, 389.
Twin crystals, formation of, J. D. Dana, xxx, 275.f
— — of Columbite, C. U. Shepard, xvii, 358.f
Twine, see [Cordage.]