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people, having been created for the education of a special class of men, we must not forget that they have had a still wider influence and use. For have they not found fitting employment for the energies of many, who in their own departments stand in the foremost rank of scientific investigators? The scientific discoverer must ever lead the way. Applied science, coming after, takes up the thread of discovery, and once guided into a useful channel industries are created and commerce spreads.
It must be evident "that practical applications cannot be made until the scientific facts or principles, upon which those applications rest, have been discovered."
Illustrations of this order of evolution are full of interest.
Black's researches on the latent heat of steam paved the way to Watt's discovery, and still later to the inventions of Stephenson. We must be grateful to Black and Watt, as well as to Stephenson, for the presence here to-day of some from a distance who wish us well.
The ancient science of chemistry yields many striking examples.
As a science it exercises a kind of creative power over the elements, setting them free, or cementing them into new relations, and as an art it is vital to the right progress and development of manufacturing industry.
More than 100 years ago Scheele discovered chlorine, a gas unknown in a free state. By combining this with lime, the well-known "bleaching
