211 



The author gives citations from several chronicles of the middle 

 ages, descriptive of the remarkable appearance of shooting stars which 

 occurred on the 4th of April, 1095, on the testimony of independent 

 witnesses both in France and England. One of them describes them 

 as " falling like a shower of rain from heaven upon the earth :" and in 

 another case, a bystander, having noted the spot where the aerolite 

 fell, " cast water upon it, which was raised in steam, with a great 

 noise of boiling." The Chronicle of Rheims describes the appear- 

 ance as if all the stars in heaven were driven, like dust, before the 

 wind. A distinct account of the shooting stars of July 26th, 1293, 

 is given by Matthew Paris. 



March 1% 1840. 

 The MARQUIS of NORTHAMPTON, President, in the Chair. 



A paper was read, entitled " On certain variations of the mean 

 height of the Barometer, mean temperature and depth of Rain, con- 

 nected with the Lunar Phases, in the cycle of years from 1815 to 

 1823." By Luke Howard, Esq., F.R.S. 



The table given in this paper contains the results of calculations 

 relating to the objects specified in the title ; cast into periods of six, 

 seven, or eight days, so as to bring the day of the lunar phase be- 

 longing to it in the middle of the time. The observations were all 

 made in the neighbourhood of London. It appears from them that in 

 the period of the last quarter of the moon the barometer is highest, 

 the temperature a little above the mean, and the depth of rain the 

 smallest. In the period of the new moon, both the barometer and 

 temperature are considerably depressed, and the rain increased in 

 quantity. The influence of the first quarter shows itself by the 

 farther depression of the barometer ; but the temperature rises 

 almost to the point from which it had fallen, and the rain still in- 

 creases, but not in an equal ratio. Lastly, the full moon again re- 

 duces the temperature ; while the barometer attains its maximum 

 mean height, and the quantity of rain is the greatest. Thus it ap- 

 pears, that during this lunar cycle, the approach of the last quarter 

 is the signal for the clearing up of the air, and the return of sun- 

 shine. 



A paper was also read, entitled " On the theory of the dark 

 bands formed in the solar spectrum from partial interception by 

 transparent plates." By the Rev. Baden Powell, M.A., F.R.S., Sa- 

 vilian Professor of Geometry in the University of Oxford. 



This paper contains the mathematical investigation of the pheno- 

 mena of peculiar dark bands crossing the prismatic spectrum, when 

 half the pupil of the eye, looking through the prism, is covered by 

 a thin plate of any transparent substance, the edge being turned 

 from the violet towards the red end of the spectrum ; and which 



