Intelligence and Miscellaneous Articles. 73 



be used without scruple at this stage of the correction of the orbit. 

 On Feb. 19, 20, and 22, the comet was excessively faint, and it re- 

 quired a great deal of caution to observe it. The single results are, 

 however, for those evenings, on the whole very consistent, the north 

 polar distances observed on Feb. 22 being subject to greater uncer- 

 tainty than the rest. It was extremely difficult to bring the comet 

 to the equatoreal wire of the instrument on that evening, though the 

 times of transit on the same evening were observed with tolerable 

 accuracy. 



3. Right Ascensions and Declinations of the Comet of Faye, ob- 

 served with the Equatoreal at the Observatory of Trinity College, 

 Dubhn, 1844. By Mr. Charles Thompson, Assistant. Communi- 

 cated by Sir W. Hamilton. 



4. Observations of the Comet of Faye. By C. Rumker, Esq. 

 Communicated by Dr. Lee. 



5. Observations of the Comet of Faye made at the Observatory, 

 Durham; lat. North 54° 46' 6" ; long. West G™ 1 8^ Communicated 

 by the Rev. Temple Chevallier. 



6. Observations made at Hartwell, Bucks. By the Rev. J. B. 

 Reade. Communicated by Dr. Lee. 



The substance of the preceding four communications will be found 

 in the Monthly Notices, vol. vi. No. 5. 



XL Intelligence and Miscellaneous Articles. 



ON THE LAWS WHICH GOVERN THE ELECTRO-CHEMICAL DE- 

 COMPOSITION OF BODIES. BY M. EDMOND BECQUEREL. 

 THE object which I proposed to myself in the essay which I have 

 the honour to submit to the Academy, is to make known the 

 laws which govern the electro-chemical decomposition of bodies. 



Mr. Faraday laid down as a principle, that when the same electric 

 current was made to pass through several metallic solutions, such as 

 those of nitrate of copper, of lead, of silver, &c., equivalent quanti- 

 ties of metal were deposited at the negative pole in each solution. 

 But this law is true only in a small number of cases, when the salt 

 is formed of an equivalent of oxide and an equivalent of acid, and 

 does not account for the effects observed in the decomposition of a 

 great number of combinations. 



As an example, I will select the hyponitrates of lead, which de- 

 posit at the negative pole two and three times and a half as much 

 lead as the nitrate for the same current. 



I have examined the decomposing action of electricity on series of 

 well-analysed bodies ; I thus successively submitted to experiment 

 all the metallic chlorides, the oxides and oxygenated water, the ace- 

 tates and the hyponitrates of lead, &c. 



All the results which I obtained have led me to the following con- 

 clusions : — 



When a binary or ternary compound is submitted to the decom- 

 posing action of electricity, the decomposition always takes place in 



