Lord Bacon remarks, “Some men think that the gratification of curiosity is the end of knowledge, some the love of fame, some the pleasure of dispute, and some the necessity of supporting themselves by knowledge; but the real use of all knowledge is this, that we should dedicate that reason which was given us by God to the use and advantage of man.” The historian of the old red sandstone, Hugh Miller, to whose researches not only we, but such men as Murchison, Lyell, Ansted, Agassiz and others, are so exclusively indebted, is a philosopher in this last category. He does not hesitate to tell us, how, as a Cromarty quarryman “twenty years ago,” he commenced a “life of labour and restraint,” a “slim, loose-jointed boy, fond of the pretty intangibilities of romance, and of dreaming when broad awake;”[35] and how, as a quarryman, he ever kept his eyes open, to observe the results of every blow of the hammer, stroke of the pick, or blast of the powder; and finding himself in the midst of new and undreamt-of relics of an old creation, preserved in “tables of stone,” he adds _his_ testimony to that of the great father of inductive philosophy, “that it cannot be too extensively known, that nature is vast and knowledge limited, and that no individual, however humble in place or acquirement, need despair of adding to the general fund.”[36] We here enter upon a marvellous field of discovery. Hitherto the forms of life we have met with have all been invertebrate. The trilobite, something between a crab and a beetle, once revelling, in untold myriads, probably on the land as well as in the water, and of which two hundred and fifty species have been brought to light, is the highest type of life with which our researches have made us familiar. We are now to begin the study of fossil fish, and to their discovery, strange forms, and characters, this chapter will be specially devoted. It was once a generally received opinion among even the most learned geologists, that the “old red sandstone,” or the “Devonian system,” was particularly barren of fossils, but the labours (literally such, “mente, manu, malleoque”[37]) of Hugh Miller have proved the contrary. “The fossils,” he says, “are remarkably numerous, and in a state of high preservation. I have a hundred solid proofs by which to establish the proof of my assertion, within less than a yard of me. Half my closet walls are covered with the peculiar fossils of the lower old red sandstone; and certainty a stranger assemblage of forms have rarely been grouped together; creatures whose very type is lost, fantastic and uncouth, and which puzzle the naturalist to assign them even their class; boat-like animals, furnished with oars and a rudder; fish plated over like the tortoise, above and below, with a strong armour of bone, and furnished with but one solitary rudder-like fin; other fish less equivocal in their form, but with the membranes of their fins thickly