66 London Electrical Society. 



5th. The Secretary then read extracts from Mr. Weekes's 

 Monthly Register for October ; — 



" The most remarkable features of the month have been the fre- 

 quent recurrence of its hea\y gales, and long-continued torrents of 

 rain ; and the major part of these were, in the language of an elec- 

 trician, decidedly of a neutral character. The quantity of rain fallen, 

 and, moreover, the immense deposit of dew during several of the 

 nights, — albeit that the amount of daily evaporation proved com- 

 paratively very small, — were unprecedented within memory, as re- 

 gards the locality of our observations." — " The neighbouring marshes 

 and low lands are inundated. Many cellars in the town (Sandwich), 

 known to have been dry upwards of sixty years, are now full from 

 a rising in the springs." 



Dec. 21. — The following papers were read: — 1st, "De- 

 scription of an Hydrostatic Galvanometer," by R. J. Iremonger, 

 Esq., M.E.S. A small bar-magnet is inserted in a cork float, 

 and so arranged as to float perpendicularly in water contained in 

 a glass tube. Around the latter is a moveable shelf, supporting a 

 De la Rive's ring, through which the current to be examined is sent. 

 The effect is, to sink the floating apparatus in direct proportion to 

 the power developed. The action of this instrument depends upon 

 the law of the pressure of liquids, which is simply as their heights. 

 Several rough models have been constructed, and have been found 

 to act well. If, upon further experiment with well-constructed in- 

 struments, the opinions advanced in this paper should be borne out, 

 the experimental philosopher will obtain an important and much 

 needed instrument. 2nd, " General Explanation of the noise of Thun- 

 der," by M. Tessan (from the ComptesRendus). The author argues 

 that when a cloud is electrized, the outward pressure of the electri- 

 city relieves it from the inward pressure of the air, in a degree pro- 

 portionate to its electrical state, and hence it expands, till the two 

 antagonist powers are in equilibrio. But if any of the electricity 

 escapes, as in a flash of lightning, the cloud instantly contracts, the 

 vapour conglomerates into drops, the air rushes with a thundering 

 noise, and the well-known deluge of rain falls. In these fundamental 

 principles the author traces several analogous phsenomena. 3rd, 

 " Notice on a New Galvanic Batter)^" by J. A. Van Melsen of 

 Maestricht (from the Bullet, de VAcad. Bruxelles). This battery is a 

 greatimprovementontheWollaston.made byplacing the platesasclose 

 as ^'gth of an inch by amalgamating the zinc, and b)' immersing the 

 whole series in one undivided trough. The great increase of power 

 obtained by these means was given in the lengths of wire fused by 

 difl^erent arrangements. A note was appended by Mr. Walker, 

 speaking favourably of the arrangement, and recommending the in- 

 troduction of the recent improvement of Mr. Smee and Prof. Grove. 

 4th, " Note upon a Modification in the Construction of Galvanic 

 Piles," by M. C'rahay. I'his note referred to certain variations of 

 the above arrangement, the principal being the soldering together of 

 the respective plates, back to back. 5th, " An Electro- Magnetic 

 Steel-yard," by Prof. Jacobi (from the author), translated from the 



