It is not therefore imagined that the general reader will find the following sketches destitute of interest, even although he should possess only a superficial knowledge of the principles and phenomena to which they refer. The professional student, on the other hand, cannot fail to obtain in them information which will prove of the utmost value to him, whether viewed as a guide, or as a stimulus to exertion; and even the accomplished naturalist may derive pleasure from the general review of the labours of those to whom he is mainly indebted for the knowledge which he possesses. The authorities which have been consulted with reference to these Lives are too numerous to be mentioned here; but the more important are pointed out as occasion presents. It may be sufficient to remark, that no modern work on Natural History would be deserving of public confidence, which did not acknowledge some obligation to the valuable labours of the French School, and of Sir James Edward Smith in our own country. The second volume, already in preparation, will be devoted to the most distinguished writers in the same department, from Pallas, Brisson, and Buffon, down to Cuvier, and will conclude with General Reflections on the present state of the science. EDINBURGH, _June 1834_. CONTENTS. INTRODUCTION. Remarks on the Estimation in which Natural History is held at the present Day, and on its Importance--Men are more conversant with Nature in uncivilized Life--The original State of Man, and his progressive Acquisition of Knowledge--General View of the Objects of Natural History: the Earth's Surface and Structure, the Ocean, the Atmosphere, Plants, and Animals--Definition of Mineralogy, Botany, and Zoology--Sketch of the Progress of Zoology: four Eras distinguished, as marked by the Names of Aristotle, Pliny, Linnaeus, and Cuvier, 17 ARISTOTLE. SECTION I. REMARKABLE EVENTS IN THE LIFE OF ARISTOTLE.