VOL. LXXIV.j PHILOSOPHICAL TRANSACTIONS. 477 



velocity of light less, and vice versa. In like manner, if the larger stars were 

 to give us in general a greater or less quantity of light in proportion to their 

 bulk, this would give us a kind of analogy, whence we might perhaps form some 

 judgment of the specific brightness of the stars in general; but, at all adven- 

 tures, we should have a pretty tolerable measure of the comparative brightness 

 of the sun and those stars, on which such observations should be made, if the 

 result of them should turn out agreeable to the ideas above explained. 



39. Though it is not improbable, that a few years may inform us, that some 

 of the great number of double, triple stars, &c. which have been observed by 

 Mr. Herschel, are systems of bodies revolving about each other, especially if a 

 few more observers, equally ingenious and industrious with himself, could be 

 found to second his labours; yet the very great distance at which it is not un- 

 likely many of the secondary stars may be placed from their principals, and the 

 consequently very long periods of their revolutions, leave very little room to hope 

 that any very great progress can be made in this subject for many years, or per- 

 haps some ages to come; the above outlines therefore, of the use that may be 

 made of the observations on the double stars, &c. provided the particles of light 

 should be subject to the same law of gravitation with other bodies, as in all pro- 

 bability they are, and provided also that some of the stars should be large enough 

 sensibly to diminish their velocity, will I hope be an inducement, to those who 

 mav have it in their power to make these observations for the benefit of future 

 generations at least, how little advantage soever we may expect from them our- 

 selves; and yet very possibly some observations of this sort, and such as may be 

 made in a few years, may not only be sufficient to do something, even at present, 

 but also to show that much more may be done hereafter, when these observa- 

 tions shall become more numerous, and have been continued for a longer period 

 of years. 



Fill. A Meteorological Journal for the Year 1782, kept, at Minehead, Somer- 

 setshire. By Mr. John Atkins, p. 58. 



This is a register of the weather, winds, barometer, thermometer, and rain, 

 3 times every day in the year. The instruments observed with were kept at a 

 house about 30 feet above high water in the Bristol channel. The whole quan- 

 tity of rain was 31.26 inches. 



IX. Description of a Meteor, Aug. 18, 1783. By Mr. T. Cavallo, F.R.S. 



p. 108. 

 Mr. C. observed this curious meteor on the Castle Terrace at Windsor, in 

 company with other gentlemen. They stood on the north-east corner of the 

 terrace, where they had a perfect view of the whole phenomenon: as every 



