The mistakes which, for a century, deprived the Union of much of its effect--the delay in granting Catholic emancipation, the folly of Free Trade, acquiesced in by Irish members, by which agrarian strife was intensified, and through which Ireland again lost the increase of population which she had gained in the first half century of Union--need not be discussed here. The fact remains that to-day Ireland is prosperous, and on the eve of far greater prosperity under a sane system of national economic policy. What is more, Ireland is in the enjoyment of practically every liberty and every privilege that is enjoyed by any other part of the United Kingdom, of greater liberty and privilege than is enjoyed by Dominions which have no control of Imperial affairs. The principle which in the case of the Colonies was applied through separate governments has, in her case, been applied through Union. It could only have been applied through Union in 1800. It can only be applied through Union to-day. Railways and steamships have strengthened the geographical and economic reasons for union; train-ferries and aircraft will intensify them still further. Meanwhile the political and strategical conditions of these islands in the near future are far more likely to resemble those of the great Napoleonic struggle than those of the Colonial Empire in its halcyon period. In one aspect, then, the Union was the only feasible way of carrying out the principle which underlay the successful establishment of Colonial self-government. In another aspect it was the last step of a natural and, indeed, inevitable process for which the history of the British Colonies since the grant of self-government has furnished analogies in abundance. It has furnished none for the reversal of that process. It is only necessary to consider the reasons which, in various degrees, influenced the several groups of independent Colonies in North America, Australia, and South Africa to unite under a single government, whether federal or unitary, thus wholly or partially surrendering the "Home Rule" previously enjoyed by them, in order to see how close is the parallel. The weak and scattered North American Colonies were at a serious disadvantage in all political and commercial negotiations with their powerful neighbour, the United States, a fact very clearly emphasised by the termination of Lord Elgin's reciprocity treaty in 1864. None of them was in a position to deal with the vast territories of the North-West, undeveloped by the Hudson's Bay Company, and in imminent danger of American occupation. A common trade policy, a common railway policy, and a common banking system were essential to a rapid development of their great resources, and only a common government could provide them. In Australia the chief factor in bringing about federation was the weakness and want of influence of the separate Colonies in dealing with problems of defence and external policy, impressed upon