100 HISTORY OF GALVANISM. 



pleasure. The following was the order in which 

 metallic wires were raised to the red heat ; plati- 

 num, iron, gold, copper, zinc, and silver, an order 

 which was conceived to be exactly the reverse of 

 their conducting power ; the places of tin and lead 

 could not be ascertained, because they melted 

 before they became red hot. 



its effects. Among the effects of this powerful apparatus in 

 generating heat, the following are some of the 

 most remarkable. Five feet and a half of plati- 

 num wire, '11 inch in diameter, was raised 

 to a red heat visible in day-light ; the same effect 

 was produced upon 84- inches of platinum wire, 

 *44 inch in diameter, and upon a bar of plati- 

 num 4- inch square, and 2^- inches long. The 

 chemical effects of the apparatus were no less 

 remarkable than its power of extricating caloric. 

 The oxide of molybdenum was easily fused and 

 reduced; the oxide of tungsten was fused and partly 

 reduced; the oxides of uranium, titanium, and 

 cerium were fused, but not reduced ; and the oxide 

 of tantalum was partially fused. The compound 

 ore of iridium and osmium was fused into a 

 globule, and iridium was formed into a globule 

 containing cavities. Box-wood charcoal was in- 

 tensely heated in chlorine and in azote, but in 

 neither case produced any effect. By heating iron 

 in contact with diamond powder, the diamond was 

 consumed ; and the iron was converted into steel. 

 Blue spinell and gadolinite were fused, and zircon 

 from Norway imperfectly so; magnesia was agglu- 



