Faraday having demonstrated by his experiments that chemical decomposition, electricity, magnetism, heat and light, are all inter-convertible and correlated forces, the inventors of the age were now ready to step forward and put these theories at work in machines in the service of man. Faraday was a leader in the field of discovery. He left to inventors the practical application of his discoveries. Prof. Henry in America was, contemporaneously with Faraday, developing electricity by means of magnetic induction. In 1832, Pixii, a philosophical instrument-maker of Paris, and Joseph Saxton, an American then residing in London, invented and constructed magneto-machines on Faraday’s principle of rendering magnetic a core of soft iron surrounded with insulated wire from a permanent magnet, and rapidly reversing its polarity, which machines were used to produce sparks, decompose liquids and metals, and fire combustible bodies. Saxton’s machine was the well-known electric shock machine operated by turning a crank. A similar device is now used for ringing telephone call bells. Prof. C. G. Page of Washington and Ruhmkorff of Paris each made a machine, well known as the Ruhmkorff coil, by which intense electro-magnetic currents by induction were produced. The production of electrical illumination was now talked of more than ever. Scientists and inventors now had two forms of electrical machines to produce light: the voltaic battery and the magneto-electric apparatus. But a period of comparative rest took place in this line until 1850, when Prof. Nollet of Brussels made an effort to produce a powerful magneto-electric machine for decomposing water into its elements of hydrogen and oxygen, which gases were then to be used in producing the lime light; and a company known as “The Alliance” was organized at Paris to make large machines for the production of light. We have seen that Davy produced a brilliant electric light with two pieces of charcoal in the electric circuit of a voltaic battery. Greener and Staite revived this idea in a patent in 1845. Shortly after Nollet’s machine, F. H. Holmes of England improved it and applied the current directly to the production of electric light between carbon points. And Holmes and Faraday in 1857 prepared this machine for use.