The mother country continues to defend its colonies, as animals defend their young and parents their children. But the polyp does not defend its offspring, nor did the earliest colonizing powers succor their colonies. While not even the armed persuasion of Cambyses could induce Tyre to make war against Carthage, neither seems to have helped the other in its need. Carthage fought savagely for her Sicilian colonies, but in her own interests, not in theirs. Though the ties between a Greek metropolis and her colonies were closer, the one did not invariably defend the other. Corcyra refused the aid her daughter city Epidaurus sought, and the latter had to find it in the grandmother city of Corinth, who considered it _her_ colony no less than that of Corcyra. The Dorian city was celebrated for her typical Greek patriotism, and she gladly assisted Syracuse to expel her Carthaginian conquerors. Rome fought for her colonies while her power lasted. France and England fought for their colonies, or rather for the possession of them, all through the eighteenth century. Spain has just fought for her last colonies, but as much against the colonists as against the foreign state that came to set them free. The mother country is also at the cost of keeping her colonies in a state of defence. The sum of £9,000 was in 1679 annually expended on the maintenance of English soldiers in Virginia and two West Indian colonies, and £1,000 on the fortifications of New York. Troops were often dispatched to assist the American colonies in special expeditions. The colonial military expenditure of Great Britain in 1859 amounted to nearly £1,200,000. In compliance with the findings of a Royal Commission, repeatedly reaffirmed by resolutions of Parliament, to the effect that the self-governing colonies ought to suffice for their own military defense, the troops were finally withdrawn in 1873, but she still maintains a garrison at Halifax and in Natal and a fleet in Australian waters, to which last the adjacent colonies contribute a fraction. Most of the self-governing colonies have at their own cost erected fortresses, and they maintain a defensive force. Two of them have stationary ships of war. They are willing and eager, moreover, to aid the mother country when she is in difficulties. When England was embroiled in Egypt or danger threatened in India and South Africa, several of these colonies offered to send, and one actually sent, troops to engage in wars in which they were not directly concerned. The head and the extremities are sometimes at variance because their interests conflict. The heart of such an empire is one. A stride has been taken toward organic unity.