—, experiments on hydrochloric acid, xi, 393.

McConnell, B. R., notice of a revolving electro-magnetic instrument, xxxiii, 188.

McCord, J. S., meteorological observations at Montreal, 1836-40, xli, 330.

MacCulloch, J., essay on remittent and intermittent fevers, xviii, 338.

McGuire, W. W., on the prairies of Alabama, xxvi, 93;

–causes of, xxvi, 96.

Machine for cleaning grain invented, iv, 387.

— and its model, relation between, E. Sang, xxiv, 264.

Machines, examination of, maximum and minimum effect of, A. B. Quinby, xii, 346.

—, electrical, see [Electrical.]