Then, this usually taciturn man went on chatting, recounting his experiments, which as a rule he confided to nobody, excepting the trees of his park, as he sometimes jestingly exclaimed. An electrical furnace being already devised, he had at first simply sought how it might be practically employed for the smelting of iron ore. In Switzerland, where the motive power derived from the torrents enabled one to perform certain work inexpensively, he had inspected furnaces which melted aluminium under excellent conditions. Why should it not be possible to treat iron in the same way? To solve the problem it was only necessary to apply the same principles to a given case. The blast-furnaces in use gave scarcely more than 1,600 degrees of heat,[1] whereas 2,000 were obtained with the electrical furnaces, a temperature which would produce immediate fusion of perfect regularity. And Jordan had without any difficulty planned such a furnace as he thought advisable, a simple cube of brickwork, some six feet long on each side, the bottom and crucible being of magnesia, the most refractory substance known. He had also calculated and determined the volume of the electrodes, two large cylinders of carbon, and his first real find consisted in discovering that he might borrow from them the carbon necessary to disoxygenate the ore, in such wise that the operation of smelting would be greatly simplified, for there would be but little slag. If the furnace were built, however, or at least roughed out, how was one to set it working and keep it working in a practical, constant manner, in accordance with industrial requirements? 'There!' said he, pointing to a model in a corner of the laboratory. 'There is my electrical furnace. Doubtless it needs to be perfected; it is defective in various respects, there are little difficulties which are not yet solved. Nevertheless, such as it is, it has given me some pigs of excellent cast iron, and I estimate that a battery of ten similar furnaces working for ten hours would do the work of three establishments like mine kept alight both by day and night. And what easy work it would be, without any cause for anxiety, work which children might direct by simply turning on switches. But I must confess that my pigs cost me as much money as if they were silver ingots. And so the problem is plain enough: my furnace, so far, is only a laboratory toy, and will only exist with respect to industrial enterprise when I am able to feed it with an abundance of electricity at a sufficiently low cost to render the smelting of iron ore remunerative.'