238 Meteorological Journal for August. 



mean temperature is chiefly owing to the warm and sultry 

 nights, in which meteors were frequently seen. In the night 

 of the 10th instant, from 9 till 12 P.M., there was a fine dis- 

 play of meteors in all directions, amounting to 42 : the lower 

 ones appeared the largest and most luminous, and several left 

 long sparkling'trains behind them. It is remarkable that these 

 meteors appeared almost at regular intervals : viz. three, four, 

 and sometimes five in quick succession about every quarter of 

 an hour. There were dark horizontal beds of cirrostratus of 

 an electrical appearance moving about at the time, which, with 

 freshening breezes from the westward, seemed to favour their 

 appearance, Two brilliant meteors, each about four inches in 

 apparent diameter, were also seen here in the nights of the 

 18th and 27th. They descended comparatively slow from an 

 altitude of 44 or 45 degrees, and in the mean time each se- 

 parated into two distinct meteors before they disappeared. 

 According to observations made here for some years past, 

 meteors have been more prevalent in August, than in any 

 other month. In August the earth has nearly arrived at its 

 greatest warmth for the year, and the exhalations from its sur- 

 face undoubtedly give additional heat to the surrounding at- 

 mosphere, in proportion to the height they ascend. Hence it 

 should seem, by the way of reasoning on the cause of this 

 phsenomenon, that by means of this additional heat, the che- 

 mical action of the gases of which the atmosphere is com- 

 posed, is excited in an unusual manner at this season of the 

 year, and that with favourable upper currents, spontaneous 

 accentions may easily occur, or meteors appear, from the ad- 

 mixture and ignition of combustible gases, aided by the pre- 

 valence of ascending and descending electrical vapours at the 

 time. In the afternoon of the 25th it was very sultry, and 

 soon after 5 o'clock a thunder-storm came on from the South, 

 accompanied by a brisk gale, very vivid lightning, several 

 loud peals of thunder, and a line double rainbow. The flashes 

 of lightning in the sunshine were light red, but the electrical 

 balls and forked lightning were blue, purple, and red. Sheet 

 lightning emanated from the clouds towards the E. and N.E. 

 in quick succession throughout the evening and night. 



Muschetoes have appeared in great numbers this month, 

 and they are still very numerous and extremely troublesome. 



The atmospheric and meteoric phauiomena that have come 

 within our observation this month, are two paraselenes in the 

 evening of the 17th, two solar and three lunar halos, eighty 

 meteors, one rainbow, thunder on two different days, and 

 sheet lightning on six evenings ; and four gales of wind, namely, 

 one from N.E,, two from S. W., and one from the South. 



Numerical 



