Meteorology — Chemistry. ^71 



culating motion. A slight sound, such as that of a bell, was sufficient to 

 restore the circulating motion. 



From these new experiments it follows, tliat the agitation of the mole- 

 cules of a li(}ui(l favours their circulating motion under the influence of a 

 slight inequality of temperature ; that this previous agitation is an indis- 

 pensable circumstance, and consequently that light produces this cir- 

 culating motion only by agitating the molecules of liquids. Hence M. 

 Dutrochet concludes, that in the phenomenon of the circulation of liquids 

 two causes intervene, one efficient, viz. the difference of temperature, the 

 other occasional, viz. light or whatever is susceptible of agitating the mo- 

 lecules of liquids. 



METEOKOLOGY. 



3. Meteor at Plymouth. — On the 30th August, between 10 and 1^ 

 o'clock, p. M. a meteor appeared at Plymouth between the stars Alioth and 

 Megrez of Ursa Major, which instantaneously lighted up the whole he- 

 misphere with uncommon splendour for a second of time, and left a short 

 train of about two degrees in length between the two stars. The light 

 was exceedingly lucid and clear. — From a Correspondent. 



II. CHEMISTRY. 



4. Reduction of Nit?Yite of Silver. — In 1826, M. Charles de Filiere 

 had occasion to have prepared by one of his pupils a considerable quantity 

 of nitrate of silver. He placed the finest crystals in unsized paper, which 

 was carelessly thrown into a card box, and consequently prevented from 

 coming into contact with bodies suspended in the atmosphere. 



Having found in the beginning of the month of November (1829, we 

 suppose,) this packet, the paper envelope of w^hich had received as usual 

 a deep violet tint, he was surprised to find that his fine crystals, without 

 having lost their form, had become plates of metallic and very malleable sil- 

 ver.-^ Ann. de Cliim. 



5. Notice on the Atacama Meteoric Iron. By Dr Turner. — In the for- 

 mer series of this Journal, vol. ix. p. 262, an analysis of the meteoric iron 

 from Atacama is inserted from the Transactions of the Royal Society of 

 Edinburgh. I was not aware at the time, that the result of a careful 

 analysis, sent to the printer for insertion, had been omitted. The compo- 

 sition of the mass in 1 00 parts is as follows : — 



Iron, - - 93.57 



Nickel, - - 6.618 



Cobalt, - - 0.535 



100.723 



6. Mineral water of R&nnely. — Ronnely lies in the province of Bleking, 

 in Sweden, 15 or 20 miles from Carlscrona, and is much frequented for its 

 mineral water. This water has a spec, gravity of 1002.55, and, according 

 to the analysis of Berzelius, contains in \OdO parts 



