Mr. R. Phillips on the Magnetism of Pewter Coils. 231 



8 inches long, the other end of the tube communicating with 

 the condenser. The only effect now produced by the steam on 

 the magnetic needle was a slight tremor, owing to the concus- 

 sions it produced in the air shaking the apparatus : the mag- 

 netism of the steam (11.) had completely disappeared. The 

 boiler was now moved until the condenser stood with regard to 

 the galvanoscope just as it did before (11.) ; opening the cock 

 of the boiler gave a strong swing to C, and a strong start to A 

 when the cock was closed. 



152. It is, I think, now quite certain, that in such experi- 

 ments as (9, 145.) the real place of magnetic excitation is in the 

 apparatus through which the steam passes before it enters the 

 atmosphere or the glass tube. 



153. The pewter coil (29.) was united to the condenser, and 

 the other end held the brass jet (9.) ; some of the pewter coil 

 had been opened out, so that there was a distance of 11 inches 

 between the nearest part of the condenser and the coil. The 

 steam was at 6 lbs. on the inch. The coil being cool, when the 

 steam was turned on the needje moved about f the length of the 

 scale to C. The coil was removed, and some steam was passed 

 through the condenser to warm it and to blow the water out of 

 the steam passages. A piece of cane, of the size before described 

 (116.), and which had been soaked for some hours in a similar 

 solution of soda, was now put in the pipe of the condenser, and 

 then the coil was quickly restored as before. On opening the 

 cock of the boiler the swing was unaltered in direction, and, as 

 far as I could judge from many experiments, in force also. The 

 fluid that escaped from the brass jet felt strongly alkaline. Con- 

 sidering the ready solubility of the oxides of tin and lead in a 

 solution of caustic alkali, it appeared to me fair to infer that this 

 magnetism was not produced by a chemical action. The follow- 

 ing experiment is, I think, conclusive on this point. 



154. A stop-cock was united to the cock of the boiler in the 

 place of the condenser. From this stop-cock proceeded horizon- 

 tally a glass tube which continued straight for 14 inches ; it then 

 descended vertically for 1^ inch, and then again horizontally in 

 the same direction as before for a distance of 1 inch ; at this place 

 the glass tube joined a straight platinum tube 5 inches long, 

 lying in the direction of the glass tube at the place where the 

 glass and platinum tubes were united ; the other end of the pla- 

 tinum tube received a glass tube, which, at a short distance 

 from the platinum tube, ascended nearly perpendicularly, and 

 then went in the first direction of the glass tube of the stop-cock : 

 the tube proceeding from the platinum was contracted at the end, 

 which finally discharged the steam to an orifice J^^ inch diameter. 

 The steam as it issued from this apparatus was received into a 



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