176 Chemistry. [Jan., 



might be swung round and round without causing more deviation than 

 half a point. 



Two interesting astronomical subjects were brought forward. 

 One afforded a fine material for discussion, and has this advantage 

 over most similar subjects, that it will be absolutely impossible for it 

 ever to be decided. The Rev. T. Webb brought forward Hansen's 

 hypothesis, that the centre of gravity of the moon did not coincide 

 with the centre of the figure of the lunar globe ; and hence there was 

 a possibility that the visible hemisphere of the moon, in reference to 

 its whole volume, was one gigantic mountain, in relation to which the 

 other side would present a region of comparative depression, con- 

 sisting of air, earth, and water, and peopled with a race of beings 

 something like ourselves. The speaker said there was considerable 

 interest in the various arguments which might be advanced on either 

 side of this hypothesis; and the members of the section therefore 

 entered into the discussion with spirit, without however, settling 

 the question one way or another. The reverend gentleman subsequently 

 exhibited a silvered glass speculum — a material which is now being 

 applied to the manufacture of telescopes with great success ; and 

 Mr. Brothers exhibited some photographs of the moon, nearly a yard 

 in diameter. 



The second astronomical paper was by Mr. Birt. It entered into 

 the subject of the telescopic appearance of the sun, and discussed the 

 various sides of the " willow-leaf ' controversy. 



Professor Fuller then read a short paper, by Mr. Waugh, on the 

 " Spectrum of Polarized Light," and another, by Mr. S. Highley, 

 describing a cheap form of electric lamp. 



The proceedings finally closed with a paper, by Mr. Birt, expla- 

 natory of a series of diagrams exhibiting the excessive variations of 

 the wind and atmosphere, as recorded by Mr. Hartnup, the Liverpool 

 astronomer, during three days before, and two days after, the great 

 storm of December, 18G3. 



Chemistry. (Section B.). 



On Tuesday, September 20, the first paper brought forward was 

 by Professor Wanklyn, on a curious example of Etherification. Mr. 

 Vernon Harcourt next read an interesting paper on the rate of 

 Chemical Change. It would be out of our power to give anything 

 like an intelligible abstract of this important paper in the space at 

 our disposal. 



Professor Roscoe then explained his Chemical Photometer for 

 Meteorological purposes, and described the results which he had 

 already obtained with it at Manchester. By means of this instrument it 

 would be easy to obtain the daily curve of the chemical intensity of 

 sunlight at any given spot. He employed for this purpose photo- 

 graphic paper prepared in such a way that the same tint on the 

 paper always corresponded with a definite amount of light. Hence, 

 if several prepared papers were exposed to a constant light for varying 



