Page:On the various forces of nature and their relations to each other.djvu/199



LECTURE I.

($1$) Page 13. The opening lecture was twice postponed on account of Dr. Faraday's illness.

($2$) Page 22. Platinum, with one exception, the heaviest body known, is 21½ times heavier than water.

($3$) Page 22. Aluminium is 2½ times heavier than water.

($4$) Pages 23 and 24. Power or Property in Water.—This power the heat by which the water is kept in a fluid state—is said, under ordinary circumstances, to be latent or insensible. When, however, the water changes its form, and, by uniting with the lime or sulphate of copper, becomes solid, the heat which retained it in a liquid state is evolved.

($5$) Page 23. Anhydrous Sulphate of Copper: sulphate of copper deprived of its water of crystallisation. To obtain it, the blue sulphate is calcined in an earthen crucible.