n6 Proceedings. 



brow of the hill. In the case referred to there is probably 

 a disposition to formation of clouds, as the clear air from 

 the sea there for the first time meets with dust and smoke, 

 which, as Aitken has shown, even in minute quantities, 

 fosters the formation of cloud in a moist atmosphere. 



^Microscopical and Natural History Section?^ 



Ordinary Meeting", December 2nd, 1889. 



Dr. ALEX. HODGKINSON, Vice-President of the Section, 

 in the Chair. 



Mr. P. CAMERON made a communication on the 

 Cynipidce of the Manchester district. There are 36 species 

 known in Britain, and of these he had found 26 species in 

 this district. 



Ordinary Meeting, December 10th, 1889. 



Edward Schunck, Ph.D., F.R.S., F.C.S., Vice-President, 

 in the Chair. 



A large photograph of the late Dr. J. P. Joule was 

 exhibited by Mr. A. BROTHERS, and was very favourably 

 spoken of by the Chairman and other members. 



Dr. SCHUSTER gave an illustration of the apparent 

 ignorance even in scientific circles of much of Dr. Joule's 

 work. It had been observed that long magnetic needles 

 give a bigger dip than short ones, and in a paper read 

 before the Society Dr. Joule explained the phenomenon as 



