TIE INTELLECTUAL OBSERVER. 



OCTOBER, 1866. 



PEISMATIC SPECTEA OF THE AUGUST METEOES, 



1866. 



BY A. S. HEESCHEL, B.A. 

 (With Coloured Plate.) 



An instrument for observing meteors was described in the 

 August number of this journal, which had for its — certainly 

 very unique., if not indeed for what must have appeared its 

 impossible — object, to examine the colours, or other peculiarities 

 of the prismatic spectrum produced by a ray of light emitted 

 from the luminous streak, or from the nucleus of a shooting- 

 star. A wide field of view ; great facility of direction, — or in 

 other words direct vision ; the means of pressing two quick 

 eyes into the service, — or, in other words, binocular arrange- 

 ment ; and, last of all, great power in the prisms, are the 

 characters without which an instrument for viewing meteor 

 spectra will be comparatively useless. A peculiar construction of 

 prisms, described in a former volume, and a binocular arrange- 

 ment of the same prisms, figured in the last-mentioned 

 number of this journal, and answering all the above con-, 

 ditions, was invented as early as the year 1864 by the writer of 

 these pages ; and a meteor spectroscope, of the pattern now 

 made by Mr. Browning, was presented by the writer to Mr. 

 Babinet, at Paris, in August, 1864; without any attempt 

 having hitherto been made, so far as the writer has been able 

 to learn, to examine the peculiarities of meteor spectra, either 

 by this or by any other means. If the problem of chemically 

 analysing the substance of luminous meteors, by means of 

 their light spectra, is not yet fairly solved, it is at all events 

 pretty certain, from the following observations, that the 

 metal sodium produces the most enduring light of the much- 

 admired trains of the August meteors ; and that at least one 

 other mineral substance (either potassium, sulphur, or phos- 

 phorus) lends its aid, but in a much less remarkable degree, 

 to produce the same luminous trains. Observations renewed 

 vol. x. — NO. III. M 



