multiplicity of testaments, prayer-books, hymn-books, &c., has also been rendered possible by the invention of printing. As darkness is favourable to crime, so the invention of gaslight has conduced to morality. The numerous sources of intellectual and moral enjoyment, developed by inventions based upon scientific discovery, have attracted mankind from more sensual and less moral amusements, and the invention of the piano-forte has operated largely in a similar manner. In many respects, the poor man of to-day can command social comforts, conveniences, and pleasures, which an emperor could not in former times. Who can estimate the amount of beneficial moral influences of an indirect kind obtained by means of modern science? The relief from pain by chloroform and other new medicines, the diminution of domestic toil by the sewing machine; the increased health and pleasure obtained by access to the country and seaside by means of railways; the diminution of anxiety resulting from more speedy conveyance of letters, and especially of messages by telegraphs, the increased pleasure of life resulting from being surrounded by objects of beauty multiplied cheaply by means of scientific processes, such as photography? The human mind cannot greatly resist impression, the various effects of scientific research necessarily {124} produce an influence upon it. Whilst great deep-seated truths make a powerful impression on the minds of philosophers, the great practical effects of science in inventions, &c., profoundly impress the mass of mankind. One of the chief influences of the discovery of important scientific truths and of their practical application in some wonderful way, such as in the telescope and microscope, phosphorus matches, photography, electro-plating, the electric light, the spectroscope, microphone, telephone, &c., is to produce a profound and wide-spread impression of the existence of a great and mysterious influence, which produces (or enables us to produce) such striking effects.