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Scientific Intelligence. 



considerable. The day threatened rain, but only a few drops fell, though 

 showers were seen farther to the west. After 5h 30' when the sun dis- 

 appeared, the whole horizon was covered with an uniform tint of a 

 bluish French grey. In the evening the moon had the same appearance 

 as the sun, and although there were faint clouds about her disc, yet 

 these clouds seemed to be illuminated neither by transmitted nor reflect- 

 ed light. The moon shone with a faint dead light, which made no im- 

 pression upon any external objects. Late in the evening, when her al- 

 titude had increased, a faint penumbral light surrounded her disc. 



At IP p. m. A great storm of wind arose, and continued all night. 

 These phenomena were observed near Melrose in Roxburghshire. 



10. Frauenhofer's Large Achromatic Telescope — This splendid instru- 

 ment, which was ordered by the Russian government for the observatory 

 of Dorpat, under the direction of that able astronomer M. Struve, is at 

 last completed ; and Frauenhofer is said to have succeeded beyond his 

 most sanguine expectations. Its focal length is 13 feet 4 inches, and the 

 aperture of the object glass is 9 inches Paris measure or 9 inches and 

 6-10ths English measure. 



MAGNETISM. 



11. Oscillations of the needle affected, by being enclosed in a copper case, — 

 We understand that, at a recent meeting of the Academy of Sciences, M. 

 Arago has shown that the magnetic needle, when disturbed, makes 

 fewer oscillations in coming to rest, when enclosed in a copper case than 

 in one of any other material, whether of metal or wood. Letter from 

 Paris. 



12. No diurnal variation of the needle at the Equator.— -M. Arago has, 

 we understand, deduced from M. Duperry's observations on the diurnal 

 variation of the needle, that there is no diurnal variation at the earth's 

 equator. 



13. Variation of the Magnetic Needle, 

 tain Smith observed the Declination of 



observed in Africa in 1823. Cap- 

 the Needle, in Africa, as follows : 



