The letter of a written constitution may survive through many decades unchanged, as has that of the Italian _Statuto_ of 1848, and as did that of the American constitution between 1804 and 1865. No (p. 045) constitutional system, however, long stands still, and least of all one of the English variety, in which there exists but little of even the formal rigidity arising from written texts. Having no fixed and orderly shape assigned it originally by some supreme authority, the constitution of the United Kingdom has retained throughout its history a notably large measure of flexibility. It is by no means to-day what it was fifty years ago; fifty years hence it will be by no means what it is to-day. In times past changes have been accompanied by violence, or, at least, by extraordinary manifestations of the national will. Nowadays they are introduced through the ordinary and peaceful processes of legislation, of judicial interpretation, and of administrative practice. Sometimes, as in the instance of the recent overhauling of the status of the House of Lords, they are accompanied by heated controversy and widespread public agitation. Not infrequently, however, they represent inevitable and unopposed amplifications of existing law or practice and are taken note of scarcely at all by the nation at large. *45. The Constituent Powers of Parliament.*--The principal means by which changes are wrought in the English constitution to-day is that of parliamentary enactment. It is to be observed that in Great Britain there is not, nor has there ever been, any attempt to draw a line of distinction between powers that are constituent and powers that are legislative. All are vested alike in Parliament, and in respect to the processes of enactment, repeal, and revision there is no difference whatsoever between a measure affecting the fundamental principles of the governmental system and a statute pertaining to the commonest subject of ordinary law. "Our Parliament," observes Mr. Anson, "can make laws protecting wild birds or shell-fish, and with the same procedure could break the connection of Church and State, or give political power to two millions of citizens, and redistribute it among new constituencies."[54] The keystone of the law of the constitution is, indeed, the unqualified omnipotence which Parliament possesses in the spheres both of constitution-making and of ordinary legislation. In Parliament is embodied the supreme will of the nation; and although from time to time that will may declare itself in widely varying and even inconsistent ways, at any given moment its pronouncements are conclusive. [Footnote 54: Law and Custom of the Constitution, 4th ed., I., 358.]