288 Galvanic ylpparalui, Tluiory of Galvanism, ^c. 



duced bv them, on the backs of my hands, was painful ; and a 

 lively scintillation took place when the poles were approximated. 

 Dutch gold leaf was not sens-ibly burned, though water was found 

 decomposable i>y wires properly affixed. No effect was produced 

 on potash, the heat being inadequate to fuse it, 



A mixture of nitre and sulphuric acid was next added to the 

 water in the troughs, afterwards charcoal from the fire was vividly- 

 ignited ; and when attached to the positive pole a steel wire was 

 interposed between it and the other pole, the most vivid ignition 

 which I ever saw was induced. I should deem it imprudent to 

 repeat the experiment without glasses, as my eyes, though un- 

 usually strong, were affected for forty-eight hours afterwards. If 

 the intensity of the light did not produce an optical deception, by 

 its distressing influence upon the organs of vision, the charcoal as- 

 sumed a pastv consistence, as if in a state approaching to fusion. 

 — That charcoal should be thus softened, without being destroyed 

 by the oxvgen of tlie atmosphere, v.'ill not appear strange, when 

 the power of galvanism in reversing chemical affinities is remem- 

 bered ; and wej-e it otherwise, the air could have no access, first, 

 he causciif the excessive rarefaction, and in the next place, as I 

 suspect, nn account ^ the volatilization of the carbon forming 

 about it a cir( umambient atmosphere. This last- mentioned im- 

 pression arose from observing, that when the experiment was 

 performed in vncuo, there was a lively scintillation, as if the car- 

 bon in an aeriform state acted as a supporter of combustion oij 

 t;he metal. 



A wire of platiiiu (No. 16) was fused into a globule on being 

 connected with the positive pole, and brought into contact with 

 a piece of pure hydrate of potash, situated on a silver tray in 

 connexion with the other pole. The potash became red hot, and 

 was deflagrated rapidly with a flame having the rosy hue of po- 

 tassurctted hydrogen. 



The great' apparatus of the Royal Institution, m projectile 

 power was from six to eight times more potent than mine. It 

 produced a discharge between charcoal points when removed 

 about four inches apart, whereas mine will not produce a jet at 

 more than three fourths of an inch. But that series contained 

 2000 pairs, mine is only about a twenty-fifth part as large. 



A steel wire of about one tenth of an incli in diameter, affixed 

 to the negative pole, was passed up through the axis of an open 

 jiecked inverted bell glass tilled with water. A platina wire, 

 No. 16, attached to a positive jiole, being passed down to the steel 

 wire, both were fused together, and, cooling, could not be sepa- 

 rated by manual force. — Immediately after this incorporation qf 

 their extremities, the platina wire became incandescent for a 

 space of some inches above the surface of the water. 



A piece 



