For one who was to take a foremost place among the naturalists of all time--that is, in the true old sense of the word naturalist, men with sympathies and insight for every department of Nature, and not mere specialists working laboriously in their own limited field of research--there could hardly have been chosen a more instructive and stimulating journey than that which was provided for Darwin by the voyage of the _Beagle_. The route lay by the Cape de Verd Islands across the Atlantic to the coast of Brazil, southward to the Strait of Magellan, and up the western side of the South American continent as far as Callao. It then struck westward across the Pacific Ocean by the Galapagos archipelago, Taheiti, New Zealand, Sydney and Tasmania, turning round into the Indian Ocean by way of Keeling Islands and the Mauritius to the Cape of Good Hope, and then by St. Helena and Ascension Island to the coast of Brazil, where the chronometrical measurement of the world, which was the ostensible object of the _Beagle's_ circumnavigation, was to be completed, and so once more across the Atlantic homewards. Almost every aspect of Nature was encountered in such a journey. The luxuriant forests of the tropics, the glaciers and snowfields of Tierra del Fuego, the arid wastes of Patagonia, the green and fertile Pampas, the volcanic and coral islets of mid-ocean, the lofty Cordillera of a great continent, arose one by one before the eager gaze of the young observer. Each scene widened his experience of the outer aspects of the world, quickened his powers of observation, deepened his sympathy with Nature as a whole, and likewise supplied him with abundant materials for future study in the life-work which he had now definitely set before himself. We must think of him during those five momentous years as patiently accumulating the facts and shaping in his mind the problems which were to furnish the occupation of all his after life.