(2) They were closely connected with the Aurora, and they were greater as the motion of the rays was more rapid and fitful and the prismatic colours more intense. Quiescent and regular arches, without changing rays or streamers, exercised mostly no influence on the needle. [Sidenote: Declination-needle, effects on.] (3) In all the disturbances the declination-needle moved towards the east, and the horizontal intensity decreased while the inclination increased. Sir John Franklin sums up his information as to the needle to much the same effect, viz. that brilliant and active coruscations cause a deflection almost invariably if they appear through a hazy atmosphere and if the prismatic colours are exhibited in the beams or arches. On the contrary, when the air is clear and the Aurora presents a steady dense light of a yellow colour and without motion, the needle is often unaffected by its appearance. [Sidenote: Parry’s experience.] Parry (Third Voyage) found his variation-needle (extremely light and delicately suspended) in no instance affected by the Auroræ; but he seems to have principally met with the quiescent form of that phenomenon. M. Lottin, the French savant (whose description of an Auroral display has been given in Chapter II.), observed in the North Sea, between September 1838 and April 1839, while the sun was below the horizon, 150 Auroræ. During this period 64 were visible, “besides many which a cloudy sky concealed, but the presence of which was indicated by the disturbances they produced upon the magnetic needle” (Lardner’s ‘Museum of Science and Art,’ vol. x. p. 189). [Sidenote: Grand displays accompanied by motion of needle to the west.] It has been remarked by some observers that grand displays of the Aurora are frequently preceded or accompanied by an extraordinary motion of the needle to the westward. Captain Maguire found at Point Barrow (1852-54) that the appearance of the Aurora in the south was connected with the motion of the magnet to the east of the magnetic north, and if in the north to the west of the same. [Sidenote: Solar disturbances and Aurora.] On an occasion in 1859 great solar disturbances were observed, the Greenwich magnets were much disturbed, and a fine Aurora was visible. [Sidenote: Cipoletti’s observation.] Cipoletti, of Florence, remarks on the strong magnetic disturbances at Vienna and Munich during the Auroræ of 4th February, 1872, and 4th February, 1874. [Sidenote: Dr. Thompson concludes that cylinders of Aurora cannot be doubted to be magnets.]