386 Dr. Gladstone on the Periods and Colours 



never since, showers occurred in February. The list commences 

 with a shower on April 4, a.d. 538; but no similar date occurs 

 for five centuries, till the four consecutive years 1093, 1094, 

 1095, and 1096, and again 1123. 



The Chinese catalogues teach a similar lesson, and are pecu- 

 liarly instructive when compared with that of M. Chasles. The 

 records of meteors kept by that remarkable people extend, with 

 some intermissions, from b.c. 687 to a.d. 1623, and have been 

 given to the European world by M. Biot*. The French philo- 

 sopher has drawn out a list of fifty remarkable showers ; and, as 

 in the list of M. Chasles, no date about August 10 or Novem- 

 ber 13 ever occurs in it. The 13th of November, however, is 

 faintly indicated towards the latter part of the Chinese catalogues, 

 but rather by the occurrence of single meteors than of showers. 

 The 25th of that month and the end of August are both more 

 frequently mentioned. The period of most common occurrence, 

 and which ranges from a.d. 830 to 933, is about July 22 ; and 

 during the Soung dynasty, from a.d. 960 to 1275, when the 

 records were most carefully kept, meteors appear to have 

 abounded two or three days later. And again, July 27 was 

 marked by star-showers in Europe in a.d. 1784 and 1785. The 

 period of March 23-29 occurs at intervals from B.C. 687 to a.d. 

 1062, both in the Chinese and European records ; the Chinese 

 also frequently notice showers of stars about October 14 ; and one 

 of the showers of this date that occurred a.d. 934 is the only one 

 that is mentioned in both lists, the only phsenomenon of the 

 kind that appears to have attracted attention at the same time in 

 both hemispheres. There are indications of a periodical shower 

 about ten days or a fortnight later in the year in the Chinese 

 records of the sixteenth and seventeenth centuries ; and Dr. 

 Lardnerf narrates similar appearances about the same time in 

 the years 1202 and 1366. 



These facts give little support to the ingenious hypothesis of 

 M. Chasles, that there may be a secular progression of these 

 periods, and that the showers of February, March, and April 

 in the middle ages may be the same as now recur in August. 

 It rather appears that the periods remain stationary sometimes 

 for centuries, but that the transit of these streams of meteors 

 through our atmosphere is liable to interruptions and changes 

 from causes which we may speculate upon, but cannot as yet 

 determine. 



Colour. — Luminous meteors generally exhibit distinct colours; 

 and these are recorded in the lists of observations. M. Poey of 



* Catalogues Generates des Etoiles Filantes et des autres m^t^ores ob- 

 serves en Chine. Memoires des Savants etrangers, vol x. pp. 129, 415. 

 t Museum of Science and Art, vol. i. p. 14 1. 



