Scientific Intelligence — Astronomy. 183 



atoms, and hence chemists had considered the peroxide of gold as a if«?r- 

 oxide. This result is confirmed by Dr Thomson, who finds that peroxide 

 of gold is composed of 



1 Atom of gold, - - - - 25 

 3 Atoms of oxygen, - - - - 3 



28 

 In this paper Dr Thomson also determines that muriate of gold con- 



2 Atoms muriatic acid, - - - 9.25 

 1 Atom peroxide of gold, - - - 28. 



5 Atoms water, - - _ - 5.625 



42.875 

 Dr Thomson then proceeds to show, in opposition to the views of Berzelius, 

 that the permuriate of tin, like the muriate of gold, is more probably a mu- 

 riate than a chloride. 



On the same day a paper was read " On the gradual changes which take 

 place in the Interior of Minerals, while the external form remains the 

 same," by William Haidinger, Esq. An extract from this paper is 

 given in the present Number, p. 126. 



2. Proceeding's of the Society for Promoting the Useful Arts in Scotland. 



March 20, 1827. — The following Gentlemen were elected Members:— r"^.' 



Ordinary. .'. 



George Swinton, Esq. Calcutta. ^-j 



Honorary. .l>^ 



David Gordon, Esq. Engineer to the Portable Gas Company, Londgj^^ 

 Rev. W. Scoresby, F. R. SS. L. and E. Liverpool. 

 Dr Thomas Traill, F. R. S. E. Liverpool. 

 * ' George Harvey, Esq. F. R. S. L. and E. Plymouth. 



Associates. 

 Mr Alexander Rose, Edinburgh. 

 There was read a letter from Davtd Gordon, Esq. to Dr Brewster, 

 on a remarkable decomposition of oil gas. See our last Number, p. 325. 



Mr SivwRiGHT exhibited a new species of file, formed by the separated 

 surfaces of chalcedony. 



The model of a new gate, by Mr John Currer, was exhibited and 

 described. This gate opened and shut by the action of the carriage that 

 approached or quitted it. 



A model of a machine for lifting and letting down weights, by Mr 

 John Currer, Viras exhibited and described. 



Art. XXXIX.— SCIENTIFIC INTELLIGENCE. 



I. NATURAX PHILOSOPHY. 



ASTRONOMY. 



1. Comet of December 1826. — This comet was discovered by M. Gam- 

 bard at Marseilles on the 27th December. The elements are as follows ; 



