between Light and Electricity. 237 



from five to twenty-five couples to traverse a liquid where two 

 other currents, put in motion by the apparatus of 100 couples, 

 intersected each other at right angles. 



6. In order to force the electric currents to intersect one 

 another under angles more or less acute in traversing a fluid, 

 I procured a tube of glass 1 1 centimetres in length ; the interi- 

 or diameter was 1 cent. ; one of its ends was closed by a plate 

 of brass, and the other was supplied with a stopper of the same 

 metal. 



In the side of this tube, and in a direction parallel to its 

 axis, three holes were made ; the first was separated 2.7 cent, 

 from the second, and the second from the third by the same 

 distance. Exactly opposite to these, but on the other side, 

 three other holes were made. We shall call the one set An- 

 terior, to distinguish them from the others, which we shall de- 

 nominate Posterior. All these holes were closed with small 

 plates or rods of brass, to which, as well as to the stopper and 

 the base of the tube were attached small pieces of lead, to es- 

 tablish, if required, the necessary communications with the 

 poles of the batteries. The apparatus being thus arranged, I 

 filled the tube with salt water ; I made the anterior band 

 which was nearest to the stopper communicate with the posi- 

 tive pole of a battery of twenty couples, and the posterior 

 band nearest to the base with the end of a wire of the galvano- 

 meter. I put the other end in communication with the nega- 

 tive pole of the same battery : the needle deviated fifteen de- 

 grees. When the circuit was broken, and the needle ceased 

 to oscillate, I restored the circulation at the same time that I 

 caused the posterior band nearest to the stopper to communi- 

 cate with the positive pole of another apparatus of twenty pairs, 

 and the anterior band nearest to the base of the tube with the 

 negative pole ; the electro-magnetic effect was still the same. 



7. I forced the current which run through the wire of 

 the galvanometer to traverse in its full length the fluid con- 

 tained in the tube, at the same time that the two other elec- 

 tric currents intersected each other in the same fluid under 

 very acute angles, as had been done in the preceding experi- 

 ment. The result was a deviation of twelve degrees ; and 

 such it was still, when I repeated this experiment, after hav- 

 ing suspended the two currents which I have mentioned. 



NEW SERIES. VOL. II. NO. II. APRIL. 1830. Q 



