which is not as much the effect of some cause, as the turning of the hands of a watch, or the parallel motion in a steam engine. It is one of the peculiar features of the history of mental philosophy, that there is scarcely ever a new principle, associated with the name of a great author, but it is shown that it has been anticipated, in some oracular sentence, probably by an obscure writer. Joseph Glanvill is pretty well known as the author of "Saducismus Triumphatus," a vindication of the belief in witches and apparitions, which must have been perused by all the curious in this species of lore. Glanvill was the author of various tracts on biblical subjects, but it was not generally known that he wrote a book on sceptical philosophy, called "Scepsis Scientifica, or, Confest Ignorance the Way to Science," until it was unearthed by the persevering inquiries of Mr. Hallam. In that book there is the passage, "all knowledge of causes is _deductive_, for we know none by simple intuition, but through the medium of their effects; so that we cannot conclude any thing to be the cause of another but from its continual accompanying it, for the causality itself is _insensible_."[84:1] This is an addition to the many instances where writers have almost, as it were by chance, laid down principles, of which they show, by neglecting to follow them to their legitimate conclusions, that they have not understood their full meaning; if it do not rather illustrate the view already noticed, that in metaphysics our assent is secured, not to general propositions as such, but to their particular applications; and that it is not in the laying down of first principles that important truths are exhibited to the world, but in those subsidiary expositions by which the discoverer endeavours to show their application.