642 Foreign and Miscellaneous Intelligence. 



of the barometer is also affected by winds from different quarters ; 

 and by taking the mean of the heights when the winds blow from 

 quarters diametrically opposite, nearly the same result is obtained 

 as when the atmosphere is tranquil, the one depressing the barometer 

 as much as the other raises it. M. Bouvard has found that the tides 

 caused in the atmosphere by the action of the moon, and conse- 

 quently the variations in the barometer due to that cause, are so 

 small, that they may, in all cases, be entirely neglected. The author 

 also gives the mean temperature of the year, and registers the kind 

 of weather which takes place, which the curious English reader may 

 wish to compare with the climate of London. At Paris there are 182 

 days in which the sky is covered with clouds, 184 in which the sky is 

 partially covered with clouds ; 142 days it rains ; 58 days of frost ; 

 180 of foggy weather ; 12 of snow ; 9 of hail, and 14 days of 

 thunder, &c. 



The mean quantity of rain on the observatory is 482 millemetres 

 (18.97 inches), and in the court of the observatory, 24 metres 

 (75.4 yards) below the platform, 365 millemetres (14.37 inches)*. 



10. CLIMATE OF ENGLAND. 



In a paper recently published in the Transactions of the Horticul- 

 tural Society of London, Mr. Knight says that he entertains no doubt 

 whatever but that our winters are generally a good deal less severe than 

 formerly, our springs more cold and un genial, our summers, and 

 particularly the latter parts of them, as warm, at least, as they formerly 

 were, and our autumns considerably warmer. In accounting for 

 these changes, our author observes, that within the last fifty years, 

 very extensive tracts of ground, which were previously covered with 

 trees, have been cleared, and much waste land has been inclosed 

 and cultivated ; and by means of drains and improvements in agri- 

 culture, the water from the clouds has been more rapidly carried off. 

 From these circumstances, the ground becomes more dry in the end 

 of May than it was formerly, and it consequently absorbs and retains 

 much more of the warm summer rain than it did in an uncultivated 

 state ; and as water in cooling is known to give out much heat to 

 surrounding bodies, much warmth must be communicated to the 

 ground, and this cannot fail to affect the temperature of the autumn. 

 The warm autumnal rains, in conjunction with those of summer, 

 operate powerfully upon the temperature of the winter, and, consist- 

 ently with this hypothesis, Mr. Knight asserts that he has observed, 

 that during the last forty years, when the summer and autumn have 

 been very wet, the succeeding winter has been mild ; and that when 

 north-east winds have prevailed after wet seasons, the winter has 

 been cold and cloudy, but without severe frost, probably owing to 

 the ground upon the opposite shores of the continent being in a state 

 similar to that on this side the Channel. 



Supposing the ground to contain less water in the commence- 

 * Mem. de 1'Acaderaie, torn. x. p. 9. 



