Page:Introductory lecture delivered at the Middlesex Hospital, October 1st, 1877 (IA b22447258).pdf/9

9 powder” is formed, and on this hangs the very existence of the great paper and cotton factories, and the daily labour of thousands of our fellow-countrymen.

We can read the same kind of history in the substance known as benzole, which Michael Faraday discovered, now fifty years since. A step forward was taken when from this aniline was prepared. But chemists regarded the little known substance as a mere chemical curiosity! and it stood for a time on the laboratory shelf useless. Busy minds, however, were working at the new compound, and as it became better known, it was found capable of yielding the most brilliant dyes. Aniline is now manufactured by the ton and our fabrics carry its colours all over the world.

Liebig had discovered chloroform years before our own countryman Simpson applied it to the relief of pain.

Sir Isaac Newton, when he divided white light into its primitive colours, little foresaw he was laying the foundation for one of the most marvellous discoveries of modern times. Yet Wollaston years after passed his beam of light through a slit instead of a round hole, and the lines of the solar spectrum were for the first time visible. It was still left to Fraüenhoffer and others to interpret their meaning, and to-day men of science are able to speak of the elements which enter into the composition of distant worlds, and you or I by the aid of the spectroscope could detect infallibly the presence of blood in solution, in amount so small