magnetographn.

1847 Philos. Trans. (Royal Soc.) 137 113 The applicability of this system of self-registration to a magnetograph was sufficiently obvious.

1883 C. Carpmael in G. J. Symons Erupt. Krakatoa (1888) 474 The three magnetograph traces were unusually steady.

1902 Encycl. Brit. XXX. 460/2 The records from ordinary Kew pattern magnetographs not infrequently show a repetition of..small rhythmic movements.

1966 McGraw-Hill Encycl. Sci. & Technol. (rev. ed.) XIV. 279/2 When used with a suitable recording unit, a set of three variometers forms a magnetograph, the simplest and most reliable of which records on photographic paper.

1992 S. P. Maran Astron. & Astrophysics Encycl. 642/1 What we know about these fields is derived almost entirely from the observation of the spectroscopic Zeeman effect with instruments called solar magnetographs.

1890 Cent. Dict. Magnetograph, the record of a magnetometer; a magnetogram.

1896 Cycl. Rev. Current Hist. (U.S.) 6 467 Professor John S. M^cKay..has obtained interesting pictures, which he calls ‘magnetographs’, resembling X-ray prints in being silhouettes of objects excluded from light, but differing from them in being produced by the action of magnets.

1887 Science (U.S.) 20 May 499/1 The earthquake was recorded automatically upon the magnetographic traces in the observatory.

1939 Geogr. Jrnl. 93 70 The magnetographic records of declination, horizontal force, and vertical force at the Dehra Dun Observatory.

1976 Nature 15 Jan. 87/2 This slow run of the signal was eliminated (especially when we compared the records of two independent magnetographs in our double-channel magnetographic system).