WCP2822

Letter (WCP2822.2712)

[1]1

68 Redcliffe Square,

London, S.W.

2I.4.[19]032. [sic]

Dear Dr Wallace,

The fundamental hypothesis of nearly every determination of the Solar Apex3 is that the ‘peculiar’ motions of the stars have no preference for any particular direction. Oscar Stumpe4 says, for instance; ‘all investigations have depended upon the assumption that star-movements obey no definable law’. (Astronomische Nachtrichten, No. 2999.)5. O. Struve6, however, introduced into his equations an expression for possible galactic rotation, but got a null result; and Stumpe imitated his procedure with a similar upshot.

If, on the contrary, the stars had a systematic drift, the course of the sun’s travel deduced on the supposition that they had none, would of course be falsified. And the error would naturally affect the velocity as well.

If you have sufficient confidence in me to trust me with your valuable M[anu].S[cript]., I will do what I can, and may at least promise to take the utmost care of it.

Your’s [sic] sincerely, A. M. Clerke [signature]

1
Page numbered 127 in pencil in top RH corner. The letter is typed.
2
Lower case letter I rather than 1 typed for the day. Year deduced from birth and death dates of author.
3
The Sun and the other stars in its vicinity take part in the general rotation of the Milky Way Galaxy (once about every 225 million years), at an average velocity of about 220 km/s. The space velocities measured for other stars then correspond to deviations from this average motion for the stars around the Sun. This motion of the Sun with respect to the local field of stars is in the direction of an imaginary point in the constellation Hercules, near the bright star Vega, called the solar apex, and the Sun is moving toward it (relative to the nearby stars) at a net speed of about 19.7 km/s. The nature and extent of the solar motion was first demonstrated by William Herschel in 1783.
4
Stumpe, Oscar (1863-1898). German astronomer, author of the article "The Motion of the Solar System in Space" (Astronomical Notes Vol. 125 pp. 385-426) (see Endnote 4).
5
Stumpe, O. (1890) Untersuchungen über die Bewegung des Sonnensystems Astronomische Nachtrichten, No. 2999-3000.
6
von Struve, Otto Wilhelm (Otto Vasilievich Struve) (1819-1905). Russian astronomer who headed the Pulkovo Observatory 1862-1889 and was a leading member of the Russian Academy of Sciences.

Editorial information

Status: Draft transcription [Letter (WCP2822.2712)]

For more information about the transcriptions and metadata, see https://wallaceletters.myspecies.info/content/epsilon

Revision history

Transcribed by O'Dell, Sandra [2015-06-01] Transcription checked by Benny, Ruth [2015-06-01] Transcription checked by Sherwood, Danni [2020-08-10]

Please cite as “WCP2822,” in Beccaloni, G. W. (ed.), Ɛpsilon: The Alfred Russel Wallace Collection accessed on 27 April 2024, https://epsilon.ac.uk/view/wallace/letters/WCP2822