466 Royal Society. 



The paper is illustrated by drawings of the specimens described, 

 with microscopic views of the shell and muscular tissue, and a re- 

 storation of the Belemnite according to the data afforded by the pre- 

 sent fossils. 



April 18. — 1. Note in addition to Mr. Gassiot's paper on the 

 "Water Battery." The author here describes an instrument which 

 he has recently constructed, and by means of which he is enabled 

 with great facility, and without the aid of Zamboni's pile, to test the 

 tension in a single series of the voltaic battery. 



2. "On the production of Ozone by Chemical Means." By Pro- 

 fessor Shoenbein, in a letter to Michael Faraday, Esq., D.C.L. 

 F.R.S. Communicated by Dr. Faraday. 



The author conceives that of the two gaseous principles which 

 are simultaneously produced during the slow action of phosphorus 

 upon atmospheric air, and which have opposite voltaic characters, 

 that which exerts electro-positive properties is composed of vapo- 

 rized phosphorus, conjoined with particles of phosphatic acid ; and 

 the other, which is electro-negative, is identical with ozone, or the 

 odoriferous principle which is disengaged at the positive elec- 

 trode during the electrolysis of water. His opinion is founded on 

 the odour of the one not being distinguishable from that of the 

 other. 



3. "Contributions to Terrestrial Magnetism." No. VI. By Lieut.- 

 Colonel Sabine, R.A., F.R.S. 



This portion of the series consists of observations made on board 

 Her Majesty's ships Erebus and Terror, from June 1841 to August 

 1842, in the Antarctic Expedition under the command of Captain 

 Sir James Clark Ross, R.N., F.R.S. It comprises the result of the 

 operations conducted during the second year of the expedition, when 

 it proceeded early in July 1841, from Hobarton to Sydney, and 

 thence to the Bay of Islands in New Zealand, remaining there till 

 November, and reaching, in February 1842, in latitude 78°, the icy 

 barrier which had stopped their progress in the preceding year. 

 Quitting the antarctic circle in March, and keeping nearly in the 

 60th parallel, they crossed the whole breadth of the Southern 

 Pacific Ocean to the Falkland Islands, where they arrived in April 

 1842. 



On a general review of the magnetic declination in the southern 

 hemisphere, the phenomena are found to present the same obvious 

 and decided features of a duplicate system as those of the northern. 

 Particular attention is given to those lines traversed by the ship's 

 course where the needle attains its maximum declination, whether 

 easterly or westerly, as affording valuable data for the estimation of 

 secular variations. The results obtained by the present expedition 

 confirm the conclusion deducible from those of previous navigators ; 

 namely, that the spaces in the Southern Pacific, distinguished by 

 certain magnetic characters, undergo a movement of translation, of 

 which the general direction is from east to west ; a direction which 

 is the opposite to that in which a similar change takes place in the 

 corresponding regions of the northern hemisphere ; namely, in the 

 Siberian quarter, where the secular movement is from west to east. 



