‎"BROOKE, CHARLES. - THE INVENTION OF THE PHOTOGRAPHIC MAGNETOMETER.‎
‎On the Automatic Registration of Magnetometers, and other Meteorological Instruments, by Photography. Received June 16, - Read June 18, 1846. (+) On the Automatic Registration of Magnetometers,....Supplement. 1846.(2 Papers).‎

‎(London, Richard and John E. Taylor, 1847). 4to. No wrappers as extracted from ""Philosophical Transactions"" 1847 - Part I. Pp. 59-68 a. pp. 69-77, 5 lithographed plates (one folding), depicting the photographic magnetometer. Clean and fine.‎

Reference : 43535

‎First printing of an importent paper in the history of meteorology, describing the invention of the Brooke-magnetometer. This new photographic drum method ensured continuous recording of geomagnetic elements, and rapidly gained use all over the world.The instrumental developments by Ronalds and Brooke establishedthe standard technique employed for magnetic observatory recording for more than a century.In 1845 Charles Brooke devised a self-recording photographic magnetometer with a light-source, a mirror for amplifying the magnet’s movement, and a drum of photographic paper. This system gradually replaced the older manual method of taking eye-observations through vertical microscope which scanned the ends of a magnetic needle" the magnetic needle itself was suspended by a bunch of silk fibersWheeler Gift No 2858..‎