178 Scientific Intelligence. 



sphere. — Great progress has been made in this important catalogue. In 

 July next 12000 observations will be sent home by Sir Thomas Brisbane, 

 and 6000 more are nearly ready. — Letter from Sir Thomas Brisbane. 



7. Mr Herschel and Mr South on Double Stars.— The valuable memoir 

 containing the observations of these two able astronomers on double stars 

 has just reached us, but too late to enable us to avail ourselves of it in this 

 Number. It forms the third part of the Phil. Trails, for 1824, and has 

 been deservedly honoured with the annual astronomical prize of the insti- 

 tute of France. Mr South has continued these observations at Passy, and 

 in the Transactions of 1825 we may expect his observations on at least 

 400 more double stars. 



8. Miss Caroline Herschel's Catalogue of Stars. — We understand that 

 this lady, already highly distinguished in the history of astronomy, has oc- 

 cupied herself since her residence in Hanover, in revising and reducing in- 

 to a general catalogue, in zones, all the twenty feet sweeps of her illustri- 

 ous brother, the late Sir William Herschel. This is a work of immense 

 labour, and will be an extraordinary monument of the unextinguished 

 ardour of a lady of seventy-five in the cause of abstract science. 



OPTICS. 



9. Lateral Refraction. — The phenomena of lateral or azimuthal refrac- 

 tion have been occasionally observed by astronomers in their geodetical ob- 

 servations. M. Schubert, in August 1823, while measuring from Tok- 

 sova the angle between the spires of the church of St Peter and St Paul 

 in Petersburgh, and the signal of Agalotowa, rain began to fall at Agalo- 

 towa at 2^ h P. M. and advanced to Toksova, and during this interval, the 

 angle alluded to increased from 88° 1' 11"0, to 88° 1' 31"2. 



10. Mr Dunlop's Reflecting Speculum. — We learn from Sir Thomas Bris- 

 bane, that his assistant, our countryman Mr Dunlop, has succeeded in 

 polishing a speculum, which bears a power of 2000 times, and Sir Thomas 

 expects that many valuable results will be made with this instrument 

 on the Magellanic clouds, and on the nebulae and clusters of stars. 



MAGNETISM. 



11. Effects of Temperature on the Magnetic Forces. — In a very able paper 

 on this subject, just published in the Phil. Trans, for 1824, Part II. Mr 

 Christie has given the following results : 



1. From 3° of Fahrenheit, and even much lower, up to 127°, the inten- 

 sity of the magnets decreased, as the temperature increased. 



2. With a certain increment of temperature the decrement of intensity 

 is not constant at all temperatures, but increases as the temperature in- 

 creases. 



3. From a temperature of about 80°, the intensity decreases very ra- 

 pidly as the temperature increases, so that if, up to this temperature, the 



