Arthur Hugh Clough died at the age of forty-two just two years after the publication of Darwin's Origin of Species. The main body of his slender volume of work was done by 1859, and it is barely probable that he knew Darwin's epoch-making study or had even heard of it. But Darwin, one must remember, climaxed a period of continuing scientific research on the results of which speculation had abundantly fed. Clough's adult years coincided with the last twenty years or so of this period. Such circumstances as the appearance of Lyell's Principles of Geology or the impact on English religious thinking of Strauss and German higher criticism, on the one hand, and the emergence of the Oxford Movement with its appeal to the principle of authority, on the other, could not but evoke from sensitive and thoughtful minds some significant response. In the period that produced Tennyson's In Memoriam, Clough's response was equally or more significant. Though their inward struggles were not unlike, the resolution for Clough differs sufficiently from Tennyson's to repay careful study of his thought. I fancy that of the two Clough's mind and the upshot of his speculation are the more congenial to the twentieth century.