Rhode Island, geological survey of, C. T. Jackson, xl, 182.

—, coal of, x, 342; xi, 78; xii, 76; xl, 187.

Rhodium in gold from Mexico, xi, 298.

Rhomb spar in Massachusetts, vii, 255; x, 18.

Rhubarb, G. W. Carpenter, ix, 91.

—, observations on, G. W. Carpenter, xiv, 33.

—, preparation of, vii, 385.

Ribaucourt, on peat, xv, 250.

Rice, how to boil, xxiii, 202.

— paper, xxiv, 207.