But as civilization advanced, and the progress of society favoured the developement of mind, when those who were no longer compelled by necessity to labour for their daily bread found leisure to look abroad with expanded views upon the wonders of the creation, the animal kingdom presented new attractions and awakened ideas which had before lain dormant. What was at first a mere sentiment of curiosity became speedily a love of science; known objects were examined with more minute attention; and whatever was rare or novel was no longer regarded with a stupid stare of astonishment and an exaggerated expression of wonder, but became the object of careful investigation and philosophic meditation. Such was the state of things in civilized Greece when the Macedonian conqueror carried his victorious arms to the banks of the Indus, and penetrated into countries, not altogether unknown to Europeans, but the natural productions of which were almost entirely new to the philosophers of the West. With the true spirit of a man of genius, whose sagacity nothing could escape, and whose views of policy were as profound as the success of his arms was splendid, Alexander omitted no opportunity of proving his devotion to the cause of science; and the extensive collections of rare and unknown animals which he transmitted to his old tutor and friend, in other words the Menagerie which he formed, laid the foundation of the greatest, the most extensive, and the most original work on zoology that has ever been given to the world. The first of moral philosophers did not disdain to become the historian of the brute creation, and Aristotle’s History of Animals remains a splendid and imperishable record of his qualifications for the task.