While the Israelites were comparatively a small and compact nation, dwelling around their tabernacle, the worshippers could easily offer their sacrifices, bringing them from their homes to the altar. But in process of time, when the nation had become a large and scattered one, its members residing at great distances, and only coming to the Temple once or twice in the year to offer their sacrifices, they would have found that for even the poor to carry their pigeons with them would have greatly increased the trouble, and in many cases have been almost impossible. For the sake of convenience, therefore, a number of dealers established themselves in the outer courts of the Temple, for the purpose of selling Doves to those who came to sacrifice. Sheep and oxen were also sold for the same purpose, and, as offerings of money could only be made in the Jewish coinage, money-changers established themselves for the purpose of exchanging foreign money brought from a distance for the legal Jewish shekel. That these people exceeded their object, and endeavoured to overreach the foreign Jews who were ignorant of the comparative value of money and goods, is evident from the fact of their expulsion by our Lord, and the epithets which were applied to them. [Illustration: JESUS DRIVES OUT OF THE TEMPLE THE MONEY-CHANGERS AND THOSE WHO SOLD DOVES.] According to some old writers, the Dove was considered as having a superiority over other birds in the instinctive certainty with which it finds its way from one place to another. At the present time, our familiarity with the variety of pigeon known as the Carrier has taught us that the eye is the real means employed by the pigeon for the direction of its flight. Those who fly pigeons for long distances always take them several times over the same ground, carrying them to an increasing distance at every journey, so that the birds shall be able to note certain objects which serve them as landmarks. Bees and wasps have recourse to a similar plan. When a young wasp leaves its nest for the first time, it does not fly away at once, but hovers in front of the entrance for some time, getting farther and farther away from the nest until it has learned the aspect of surrounding objects. The pigeon acts in precisely the same manner, and so completely does it depend upon eyesight that, if a heavy fog should come on, the best-trained pigeon will lose its way. [Illustration: THE ROCK DOVE.]