1818.] kept at the Academy of Gosport. 167 



time more) almost every sunny and fair day : this change we 

 suppose to arise purely from solar influence ; but the aggregate 

 diurnal increase does, in all probability, arise from a combination 

 of causes, as caloric downwards, non-electric winds, &c. &c. 3cc. 

 The annual mean diurnal temperature of the upper room in the 

 Observatory, where no fire was kept, is about 4° higher than 

 the annual mean diurnal temperature without door; and the 

 annual mean nocturnal temperature 5° higher. This difference 

 undoubtedly arises from the loss of the calorific or dark rays 

 that steal imperceptibly on, and raise the thermometer placed 

 without door. We make this remark merely to point out to 

 those who keep regular journals of the weather, the real differ- 

 ence that will arise from registering from a thermometer within, 

 and from a Six's placed in the free air in a northern aspect out 

 of the rays of the sun ; and we are confident in stating that 

 similar observations made in the same city, town, or village, 

 will ever vary considerably, without regard to- .placing the instru- 

 ments for meteorological purposes. 



Atmospheric Phenomena. 



The following atmospheric phenomena have come within our 

 observation this year, and we have selected them, as a piece of 

 curiosity, from our monthly meteorological journals, published 

 in the 37th and 38th volumes of Naval Chronicle, namely, 

 lightning, 14 different days ; thunder, 1 1 ; hail, 12 ; snow, six ; 

 and a quiescent barometer, six. 42 gales of wind from different 

 quarters, viz. four from the N., two from the N.E., 17 from the 

 S.W., 10 from the W., and nine from the N.W. 14 rainbows, 

 eight of which were perfect with their proper colours. 16 solar 

 halos; 15 lunar halos ; 20 lunar coronas; one lunar iris; and 

 one coloured paraselene, which appeared on July 30, between 

 11 and- 12 P.M. 18 small meteors, commonly called falling or 

 shooting stars, and two large ones, half the apparent size of the 

 moon at her greatest altitude : also two Aurora Boreales, or 

 northern lights. All the modifications of doud adopted in the 

 nomenclature, appeared here on September 1. 



Ocular Appearances. 



Solar Halo.— The most beautiful of the solar halos appeared 

 on June 5, from seven till half-past nine, A.M. on the vesiculce 

 of a thin vapour or haze, which was at that time descending 

 slowly into the lower medium; it measured 44° in diameter 

 horizontally, and several of the prismatic colours that formed it 

 were tolerably bright : the atmosphere, from the interior edge of 

 the halo to the light yellow concentric corona immediately around 

 the sun, was, to all appearance, darker and denser than that 

 outside of the coloured circle. At one P.M. on the following 

 fiay, two semicircular parts of a halo of the same diameter 



