—, leather, fabrication of, iv, 193.

—, universities, xx, 176.

Rust, preservation of iron from, xix, 203; xxi, 150; xxii, 382; xxiii, 199, 383.

—, means of preserving from, by caoutchouc, vi, 398.

Ruthenium, a new metal from the Ural, xvi, 384; xlviii, 401.

Rutile, in Connecticut, iv, 55.

—, in Massachusetts, i, 116, 134; v, 405; vii, 58; xii, 259; xx, 170.

—, in New Jersey, ix, 245.

—, in New York, xxi, 325.

—, in Pennsylvania, v, 41; xiv, 5, 14.