[333] Outlines of Astronomy, III. Sec. 13, 140.
[334] Thus several of the best telescopes in the world are rendered nearly useless by the passage of heavy railroad trains in their vicinity.
[335] Somerville's Physical Sciences, VI.
[336] Cosmos IV. 477. Phillips' Address to the British Association, 1865.
[337] North British Review, LXV.
[338] Annual of Scientific Discovery, 1864, 158.
[339] Cosmos I. 109.
[340] Cosmos IV. 501.
[341] Cosmos IV. 378.
[342] Harper's Magazine, June, 1872, p. 149.