Footnotes

[1]. The mean distance of the earth from the sun is 95,000,000 miles, but to avoid the inconvenience of large numbers, it is assumed to be the unit of distance; hence the mean distance of Mars is 1·52369, or 1·5 nearly, that of the earth being = 1.

[2]. The obliquity given in the text is for the year 1858.

[3]. Sir John Herschel remarks that there are just as many thousands of feet in a degree of the meridian in our latitude as there are days in the year, viz. 365,000.

The Greenwich Observatory is in N. lat. 51° 28ʹ40ʺ.

[4]. Or more correctly 3422ʺ·325 and 238,793 miles, as deduced from Mr. Adams’ more accurate calculations.

[5]. Neptune was discovered in the year 1846.

[6]. The satellites of the two great planets on the farthest verge of the solar system form a singular exception to this law.

[7]. See the chapter on the Tides and Currents in the ‘Physical Geography,’ by the author, 4th edition.

[8]. Sir John Herschel on Meteorology.

[9]. Bakerian Lecture, by Michael Faraday, Esq. Phil. Trans. 1857.

[10]. See page [104].

[11]. M. Marbach of Breslau.

[12]. ‘Meteorology,’ by Sir J. Herschel.

[13]. This theory of heat and motion originated with Mr. Joule, of Manchester, who has maintained it with the greatest talent, both by experiment and analysis; and it has had an able advocate in Professor W. Thomson, of Glasgow.

[14]. To this remarkable man the world is indebted for the locomotive railway system, which is rapidly advancing the civilization of mankind. Britain may well be proud of its working classes, which can produce such men; and Mr. George Stephenson is not the only one; there are many others; but no man has ever had greater influence by his labours and discoveries on human affairs.

[15]. ‘Correlation of the Physical Forces, by W. R. Grove, Esq.,’ one of the most remarkable and talented works that has appeared, to which the author with pleasure acknowledges her obligations.

[16]. “Eripuit fulmen Cœlo, sceptrumque tyrannis,” is the inscription on a medal struck in honour of Franklin.

[17]. Faraday.

[18]. Professor Matteucci still expresses doubts on this subject, but has not yet finished his experiments.

[19]. Babbage.

[20]. Phil. Mag. for May 1858.

Transcriber's Notes

Some corrections were made to the original text. In particular, punctuation was corrected without further note. Inconsistent spelling and hyphenation was retained unless noted otherwise. There were two [Notes 189] in the original; this was retained as printed. Spelling of Index entries was changed to reflect the body text where inconsistencies were found. Index page numbers were corrected where errors were found. Further corrections are noted below:

p. [50] 0·005·1449 -> 0·0051449

p. [61] 24,000 -> 240,000

p. [62] M. Leverrier -> M. Le Verrier

p. [84] in mean solar day -> in a mean solar day

p. [96] syzigies -> syzygies

p. [115] arrising -> arising

p. [120] Herchel -> Herschel

p. [123] generally know -> generally known

p. [159] Fraunhoffer’s -> Fraunhofer’s

p. [168] contaary -> contrary

p. [214] oxyde -> oxide

p. [216] aperature -> aperture

p. [296] M Niepce -> M. Niepcé

p. [306] torrecelian -> Torricellian

p. [307] potass -> potash

p. [350] de Roux -> le Roux

p. [423] Β -> β

p. [447] areal -> aërial

p. [456] perigree -> perigee

p. [471] 108° -> 180°

p. [478] Meissier -> Messier