Mr. R. Phillips on the Magnetism of Steam. 287 



opened, S and V being previously opened, the needle swung 

 to C ; and to A when the cock of the boiler and S were opened, 

 and V then opened. When the iron was removed, the swings 

 both to C and A were much diminished. 



139. The coil was removed from the condenser and turned 

 about in a direction parallel to the needle, so that the steam 

 could enter through V and escape through the combination 

 of T-pieces at the other end of the pipes; the steam being, 

 in fact, blown through the coils in a direction opposite to that 

 of the last experiment. Opening V and S, and then opening 

 the cock of the boiler, gave a swing to C. Opening V and 

 the cock of the boiler, and then letting out the steam by open- 

 ing S, gave the swing to A. The iron core was not used with 

 this arrangement. 



140. The coil was moved through an angle of 180° as be- 

 fore (19.)* Both swings were now reversed, as compared with 

 the former experiment; that is, using the steam as before, the 

 swing to C became a swing to A, and the swing to A became 

 a swing to C. 



141. The pewter coil (29.) was united to the condenser by 

 a piece of brass, the steam-way of which was of larger dia- 

 meter than the bore of the coil. The steam circulated in a 

 contrary direction to the hands of the watch. When the cock 

 of the boiler was opened, the swing was to A and rather 

 strong. 



142. The other end of the pipe of the coil was united by 

 the same piece of brass to the condenser, and the steam cir- 

 culated in the same direction as the hands of the watch ; the 

 swing was still to A. 



143. A stop-cock was now placed on one end of the tube 

 of this pewter coil, and the other end was affixed to the con- 

 denser, as in the two preceding experiments ; the steam cir- 

 culated in a direction contrary to the hands of the watch ; also 

 the iron core was placed in the coil. The stop-cock being 

 open and the coil cool, turning on the steam produced a 

 strong swing to C. The stop-cock was now closed with the 

 cock of the boiler open ; on opening the stop-cock at the 

 proper positions of the needle, a swing to A was obtained on 

 opening the stop-cock, but it was not nearly so strong as the 

 corresponding swing with the double coil. The diameter of 

 the steam- way of the stop-cock was ^ inch. 



144. The iron was now removed. The swing to C when 

 the coil was cool, although less, was still very good, as one 

 puff sent the edge of the needle rather more than the whole 

 length of the micrometrical scale. The swing to A was, how- 

 ever, very feeble ; and it required about ten puffs to produce 

 a swing one-third the length of the scale. 



