502 Mr. R. Phillips on the Magnetism of Steam, 



dition is fulfilled, and I continue to deny it. Hence Professor 

 Challis is mistaken in supposing that I admitted what before 

 I denied, and denied what before I admitted. 



It is not my intention to attack Professor Challis's new 

 views respecting the theoretical velocity of sound ; because if 

 Professor Challis and I cannot agree on what to my own 

 mind seems so plain a matter as the theory of spherical waves, 

 I see little chance of our agreeing on the subject I have men- 

 tioned. 



I am, Gentlemen, 



Your obedient Servant, 

 Pembroke College, Cambridge, G. G. StokeS. 



June 6, 1849. 



LXXIII. On the Magnetism of Steam. 

 By Reuben Phillips, Esq.* 



1 . rp^HE following investigation has resulted from an at- 

 -I- tempt made with a view to the better understanding 

 of the relation between electric and magnetic forces, by ascer- 

 taining whether the only form of the electric current, the na- 

 ture of which, principally from the researches of Dr. Faraday, 

 is very completely comprehended, possesses the usual magnetic 

 properties. In this I was baffled (but the way is now open) by 

 an unexpected phsenomenon, the nature of which it became of 

 primary consequence to develope, and which forms the subject 

 of the present paper. 



2. A little wooden stick was laid across the mouth of a 

 small Bohemian beaker ; the stick was placed parallel with 

 the bottom of the glass, and held in its position with sealing- 

 wax : the beaker was 3*5 inches high. A common sewing- 

 needle No. 7, and another No. 8, were magnetized and stuck 

 through a slip of thin card, the north end of one magnet being 

 opposed to the south of the other, the needles being two inches 

 apart. This partially astatic arrangement was suspended from 

 the stick by a single fibre of silk, and the length of the fibre 

 between the points of suspension was one inch. The needles 

 made one vibration in about two seconds. I found if the 

 needles were much more astatic than this, they were very 

 subject to slow irregular variations of position, which appeared 

 to proceed from a twisting of the silk arising from changes in 

 its hygrometric or calorific condition. The mouth of the 

 glass was closed with a card cover furnished with a rim. 



3. The beaker was now placed on the stage of a microscope 



* Communicated by the Author. 



