On the Connexion of the Physical Sciences

James, Colonel, measurements of, in the General Survey of Great Britain, 47; density of the earth determined by, 58. Jamin, M., remarks of, on substances producing elliptical polarization, 193. January, epoch of its beginning the year, 85. Jews, denominations of time in their calendars, 85. Josephstadt, discovery of a comet from, 367. Joule, Mr., heat considered a mechanical force by, 275; his view of elastic force, 276; amount of latent force in a pound of coal, computed by, 278; furnishing data to Professor Thomson, 279; quantity of heat generated in a unit of time by electricity computed by, 302; powerful magnet obtained by electricity, 315; electric machines constructed by, 328; experiments proving heat and mechanical power convertible, 329. Jovial system, mass of the whole, 55. Julian Calendar, year of, the first of our era, 86. June, 1833, reappearance of Saturn’s rings, 67; coincidence of times in, 84. Juno, the diameter of, 56; astronomical tables of, 63.