On no occasion can such a subject be presented to a contemplative mind, without filling it with awe and wonder; but the circumstances under which these reflections are presented to us, in the last days of our philosopher, impress upon them an almost oracular solemnity. When we remember that while the mind of the philosopher was thus engaged in identifying the processes of decay with those of renovation in the system of nature, his body was palsied, and the current of his life fast ebbing, we cannot but admire that active intelligence which sparkled with such undiminished lustre amidst the wreck of its earthly tenement. In the extracts which have been introduced from this last work, I trust the pledge that was given in the earlier part of these memoirs, has been redeemed by showing that a powerful imagination is not necessarily incompatible with a sound judgment, that the flowers of fancy are not always blighted by the cold realities of science, but that the poet and philosopher may, under the auspices of a happy genius, mutually assist each other in expounding the mysteries of nature. It cannot be denied, as a general aphorism, that the tree which expands its force in flowers is generally deficient in fruit; but the mind of Davy, to borrow one of his own metaphors, may be likened to those fabled of the Hesperides, which produced at once buds, leaves, blossoms, and fruits. The happy effects resulting from this rare and nicely adjusted combination of talents, offer themselves as interesting subjects of biographical contemplation, and they can be studied only with success by a comparative analysis of different minds. That the superiority of Davy greatly depended upon the vivacity and compass of his imagination cannot be doubted, and such an opinion was well expressed by Mr. Davies Gilbert, in his late address to the Society:--"The poetic bent of Davy's mind seems never to have left him. To that circumstance I would ascribe the distinguishing features in his character and in his discoveries:--a vivid imagination sketching out new tracks in regions unexplored, for the judgment to select those leading to the recesses of abstract truth." I have always thought that the mind of the late Dr. Clarke, the Mineralogical Professor of Cambridge, was little less imaginative than that of Davy; but it was deficient in judgment, and therefore often conducted him to error instead of to truth. Dr. Black was not deficient in imagination, and certainly not in judgment; but there was a constitutional apathy, arising probably from ill health, which damped his noblest efforts.[121]