Transcriber's Notes
Obvious typographical errors have been silently corrected but variations in hyphenation and all other spelling and punctuation remains unchanged.
The following corrections have been made:
Réamur has been corrected to Réaumur throughout.
Page 94 “There are seven primary colours in the sunlight, which is white. These can be divided or “dispersed,” and the shortest rays of the spectrum are found to be red, the longest violet.” has been corrected.
Page 109. “If, for instance, we place on a disc covered with blue and red sectors of equal size, a black disc, of which the sectors are alternately filled in or empty, the disc, as it turns round, will appear blue if the black sectors of the upper disc exactly cover the [red] sectors of the lower disc; and it appears red, if, on the contrary, the blue sectors are covered with the black;” [red] has been added.
Page 238. The footnote Monvel’s “Course of Physics.” appears, but there is no reference to it in the text.
Page 533. The time of revolution of Saturn’s Moons was given in d. h. sec., this has been corrected to d. h. min.