See how the field of human knowledge is extended. Within the last fifty years there is scarce a branch of knowledge, even in those which have been explored for hundreds of years—classical learning, for example—which has not received some new and important additions. But not only this; it may be said that new sciences have been discovered. Who, seventy or eighty years ago, thought or heard of the name of geology, or of men like Cuvier, who by their genius have brought back to us the forms of long-extinct animals, and the state of the earth as it must have existed thousands of years ago? Who could have imagined that in art such vast resources should have been opened up to us, as, for instance, the now-familiar science of photography supplies? Who would have imagined that railways, which have enabled us at so quick a rate to have communication with all parts of the country, would become a study of well-regulated curiosity; or that the instantaneous power of transmission which we possess in the electric telegraph should be imparted to the whole of the people who now crowd these busy shores? Some of the noblest triumphs of science, however, do but show the shortsightedness of man, and seem to dictate to him that great results can only be obtained by gradual and patient labour, as if to keep in check his overweening conceit. This is illustrated in the discovery of Voltaism. “When Galvani,” says Lord Brougham, in his powerful manner, “observed the contortions of the muscle in a dead frog, or even when Volta gave an explanation of them, how little could it be foreseen that the discovery would lead not only to the decomposition of bodies which had resisted all attempts to ascertain their constituent parts, and bring us acquainted with substances wholly unlike any before known, as metals that floated in water and took fire on exposure to the air; but, after having thus changed the face of chemical science, should also impress a new character upon the moral, judicial, and political world! Yet this has undeniably been the result of the discovery made by Volta.”