24 REPORT — 1870. 



On Shooting-stars. By the Eev. E. Main, M.A., F.E.S., F.R.A.S. 



The author presented to the Ai=sociation the observations of meteors and shooting- 

 stars made almost exclusively by Mr. Lucas, at the Observatory, during the past 

 year. The whole number of meteors seen and observed during the year is about 

 300, of which, of course, a considerable number belong to the November and August 

 groups. Next to these, the month of October seems to be the most fruitful, while, 

 on the contrary, in January, February, and March scarcely any were seen. This, 

 however, may be due to the cloudy state of the sky which generally prevails at 

 Oxford in the early part of the year. Of those observed, more than fifty were as 

 bright or brighter than stars of the first magnitude ; six were as bright as Jupiter ; 

 one, observed on November 4, 1869, was estimated as equal to one-sixth of the full 

 moon ; and one, on December 29, as equal to one quarter, the sky being overspread 

 in the latter case by light clouds. Two remarkable meteors were seen on Novem- 

 ber 6, one of which was observed (by a person not connected with the Observatory) 

 to burst with noise near the north-west horizon. On July 8 one was seen to burst, 

 though the sky was so overcast with nimbus cloud that no star could be seen. 



On the Laws of Star-grouping. By E,. A. Proctor. 



The aim of this paper was to show that the stars are grouped together in varied 

 forms, separated by comparatively barren distances, and that the observed pecu- 

 liarities of stellar distribution are due to real laws of aggregation and segregation. 



Electricity and Magnetism. 



On Faure's Battery. By C. Becker. 



Faure's element is a modification of that known as Bimsen's, the poles consisting 

 of carbon iu strong nitric acid and amalgamated zinc in dilute sulphuric acid. In 

 Bunsen's ordinary form of carbon element the carbon pole is immersed in a vessel 

 holding a considerable quantity of nitric acid, which, as it becomes deoxidized by 

 the electrolytic action of the current, liberates nitrous-acid gas, which rises into the 

 air, rendering it unwholesome to breathe and destructive to most metallic apparatus 

 in its neigliboiu-hood. The purjiose of Faure's battery is to obviate those draw- 

 backs. This is effected by confining the nitric acid inside the carbon pole, and al- 

 lowing only sufficient acid to percolate through it in order to keep up the necessary 

 electrolytic action of the element. The carbon pole is made in the form of an ordi- 

 nary bottle, and is provided with a carbon or platinum stopper to which the binding- 

 screw of the pole is attached. This bottle, which at once fulfils the functions of 

 pole and porous diaphragm, is placed concentrically in the interior of a cylinder of 

 amalgam.ated zinc; and the whole is contained in an earthenware jar. When set 

 up for action the bottle is nearly filled with nitric acid, and the space containing the 

 zinc between the bottle and the outer jar to the required height with sulphuric 

 acid. The slight liberation of gas within the bottle causes a sufiicient pressure to 

 be exerted upon the nitric acid to force it gi-adually through the carbon. 



In this way the exterior of the carbon pole remains immersed in a very thin layer 

 of nitric acid immediately opposite the zmc, which is in course of dissolution of the 

 dilute sulphuric acid. In point of constancy the element is superior either to 

 Bunsen's or Grove's, because the body of nitric acid remaining protected within 

 the bottle does not become weakened as in the case with those forms of element in 

 which the fluids are exposed in larger quantities and separated by porous 

 diaphragms. It acts also entirely without any disengagement of gas into the air, so 

 that it may be used in any room without disagreeable consequences. A variety 

 of forms might no doubt be given to these elements, which would enable them to 

 fulfil the desired object. Those exhibited were designed and manufactured by 

 Messrs. Elliot Brothers, and are found to be convenient for experimental purposes 

 aa well as for use in telegraph ofiices. 



