162 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



easily be determined, to calculate the magnetism at any 

 point of any magnet whatever. 6 B^ LXXXI., 11, 177. 



MAGNETIC OBSEKVATIONS IN THE INDIAN OCEAN. 



It is noted that the magnetic observations made at twelve 

 stations occupied by transit of Venus parties are all due to 

 the observers trained at Stonyhurst. At each of these sta- 

 tions, for about five months, observations were made every 

 two hours during the day and night; and these will, it is 

 hoped, afford a fair knowledge of the spring and summer 

 weather in the Pacific and Indian Oceans. Quart. Jour. 

 British Met. Soc, 1876, 81-87. 



MAGNETIC MAP OF FRANCE. 



The Annuaire of the Bureau of Lomxitudes for 1876 con- 

 tains a magnetic map of France, prepared by Marie Davy. 

 It is the intention hereafter to annually publish this same 

 map with such corrections as it needs from time to time. It 

 would be very highly appreciated in America, if our own 

 Nautical Almanac Office would add a similar work, showins: 

 the distribution of terrestrial masinetism in the United States, 

 to its present publication, which, while principally astronom- 

 ical, contains something having reference to the tides and to 

 terrestrial physics. Annuaire Bureau of Longitudes, 1876, 

 326. 



ON THE DEVIATION OF THE COMPASS. 



Belavenetz, as the Director of the Compass Observatory of 

 Cronstadt, has invented an apparatus for annuling the influ- 

 ence upon the ship's compass of the permanent and induced 

 magnetism of the ship. The application of this apparatus 

 has therefore the result of forcing the ship's compass to indi- 

 cate always the true meridian, no matter in what direction 

 the ship may head. The arrangement of the device by Be- 

 lavenetz, in fact, completely eliminates the semicircular and 

 the quadrantal deviations, so that, by means of horizontal and 

 vertical magnets and powerful iron cylinders, the deviation 

 on board of a ship, the inclination, and the total magnetic 

 force are brought back to their normal values for the portion 

 of the earth in which the ship happens to be. Austrian Hy- 

 (Jrog. Mitth. 



