[ 1*2 ] 

 XXVIII. Proceedings of Learned Societies. 



ROYAL SOCIETY. 



May 17-— W^ H. WHITE, Esq. was ejected from the Society : 

 ** • and a paper was read, " On the secondary de- 

 flexion produced in a magnetized needle by an iron shell, in con- 

 sequence of an unequal distribution of magnetism in its two branches; 

 discovered by Capt. Wilson, R.N. ; by Peter Barlow, Esq. F.R.S." 



A paper was also read, entitled, " On the difference of Meridians 

 of the Royal Observatories of Greenwich and Paris; by Thomas 

 Henderson, Esq." Communicated by Mr. Herschel. 



Mr. Henderson has detected an error of one second in the reduc- 

 tion from mean to sidereal time of some of the observations officially 

 made for the purpose of determining the difference of the meridians 

 of these two observatories, in July \>2n. This connection redeems 

 the result of the observations of July 21 from the suspicion that 

 attached to it; produces a change of one-tenth of a second in the 

 final result of the whole operation, giving 9" 2P"5 for the most 

 probable difference of longitudes between the two observatories; 

 and also triples the value of the result obtained by narrowing the 

 extreme range of the experiments, from 65 to 0''21. 



A letter was read from Mr. C. Rumker, of Paramatta, giving an 

 account of several series of observations made at the observatory 

 there; consisting of the following: 



1. Original and correctly reduced places of the comet of 1826, 

 as observed from September 4 to October 5. 



2. Mean places of the stars with which the comet was compared. 



3. Elements of the comet as computed by Mr. Rumker. 



4. A catalogue of mean places of stars near the orbit of the 

 comet, about 58 in number, for Jan. i, 1827, mostly of the 7th 

 magnitude. 



5. The latitude of the observatory, 33° 48' 50"-45 S., as found 

 by reflexion with the mural circle. 



May 24. — The Right Hon. C. Watkin W. Wynne was elected 

 into the Society : and a paper was read, entitled, " On destroying the 

 fire-damp in mines by the chloride of lime ; by F. Fincham, Esq." 

 Communicated by Mr. Children. 



The very low price at which chloride of lime is produced in this 

 country, led the author, who is a manufacturer of that substance, 

 to several useful applications of it in large quantities. The first 

 which occurred to him was the destruction of the stench of bilge- 

 water in ships, and the correction of the confined air in their holds ; 

 both which he has successfully effected in the dock-yards at Dept- 

 ford and Chatham. After describing the experiments on this sub- 

 ject, he proceeds to relate a series instituted for the purpose of de- 

 stroying fire-damp in coal-mines. 



On March 17th, in a part of the Bradford colliery, where the 

 workmen, during the foregoing part of the week, had been obliged 

 to use the safety-lamp, he sprinkled chloride of lime. On the I9th, 

 though the damp had been collecting during the intermediate Sun- 

 day, 



