542 On the Luminous Phenomena of the Voltaic Battery. 



it is covered with iron. That at the negative pole has gained 

 360 milligrammes ; it is also covered with metallic iron. The 

 plate of iron interposed has lost 327 milligrammes, and traces 

 of copper are perceived in it. 



" 3. An iron sphere at the positive pole ; a cone of coke, 

 prepared according to Bunsen's manner, at the negative pole. 

 The distance is 3 millimetres at the beginning of the experi- 

 ment : after it had been continued for 33 seconds the iron had 

 lost 32 milligrammes. The coke had lost 5 milligrammes, 

 and it was nevertheless covered with iron, or rather with 

 steel. 



" 4. An iron sphere terminated the negative electrode ; a 

 Bunsen's cone of coke formed the positive. The iron had lost 

 in 33 seconds 80 milligrammes, nearly the same quantity as 

 in the preceding experiment, of which this is the inverse. 

 The coke at the positive pole had lost 25 milligrammes. The 

 margins of the excavation of the coke were remarkable for 

 their hardness ; they blunted the best files. 



" It seems to me from all this, that there is no doubt that 

 the matter is projected from the two poles at the same time. 



" It remains to be ascertained whether their quantity is the 

 same from both sides. The two following experiments appear 

 to me to render this equality doubtful ; but this point must be 

 decided by further experiments. 



" 5. I terminate the positive pole with a plate of copper, 

 the negative pole with a point of the same metal. The cop- 

 per point melts and runs; the plate gains 22 milligrammes. 

 As soon as the electric spark has established the current, a 

 superb bluish flame is projected against the plate. 



" 6. The copper plate forms the negative pole, the point 

 the positive pole: the point melts, and the plate gains 30 

 milligrammes ; but the light is less intense, and the current 

 ceases when the distance between the electrodes is only slightly 

 augmented by the fusion of the point; whilst in the fifth ex- 

 periment, the current has not ceased to pass until the fusion 

 of the point has increased the distance between the electrodes 

 to two centimetres, a distance which, at the commencement of 

 the experiment, was only as many millimetres*. 



i( If, between two spheres or a plate and a sphere, I make the 

 distance small enough, I produce, without previous contact, 

 by means of a battery, a metallic wire which joins the two elec- 

 trodes to each other, and by which the current is continuedf. 



" Finally, I recommend one more experiment to your at- 

 tention. It appears to me to demonstrate the repulsion which 



* An important point is not stated in this experiment, viz. whether the plate 



were underneath, ahove, or laterally placed with regard to the point. — Ed. 



t This seems not to be consistent with the statement in paragraph 4. — Ed. 



