Ticonderoga has more than once stayed the waves of northern invasion; and we know of no change in the art of war, or in the condition of the country, that renders less important than formerly the advantages of an intermediate point of support between Albany and the Canadian lines.  Indeed it would seem that the connection of the Hudson with the lake by the northern canal had even increased the value of such a point.

It would seem, moreover, that the great value of a central depot near Albany would warrant a resort to the best means of security which can be afforded by defensive works.  Here we already have one of our largest arsenals of construction; here are to be located magazines for the collection and deposit, in time of peace, of gunpowder; here, in time of war, is to be formed the grand military depot for our whole northern armies; and here is the point of junction of the lines of communication of our northern and eastern states, and the great central rallying point where troops are to be collected for the defence of our northern frontier, or for offensive operations against Canada.  Such a place should never be exposed to the coup-de-main of an enemy.  The chance operations of a defensive army are never sufficient for the security of so important a position.  We do not here pretend to say what its defences should be.  Perhaps strong tetes-de-pont on the Mohawk and Hudson rivers, and detached works on the several lines of communication, may accomplish the desired object; perhaps more central and compact works may be found necessary.  But we insist on the importance of securing this position by some efficient means.  The remarks of Napoleon, (which have already been given,) on the advantages to be derived from fortifying such a central place, where the military wealth of a nation can be secured, are strikingly applicable to this case.

But let us look for a moment at what is called the western plan of defence for our northern frontier.

Certain writers and orators of the western states, in their plans of military defence, would have the principal fortifications of the northern frontier established on Lake Erie, the Detroit river, the St. Clair, and Lake Huron; and the money proposed for the other frontier and coast works, expended in establishing military and naval depots at Memphis and Pittsburg, and in the construction of a ship-canal from the lower Illinois to Lake Michigan,—­for the purpose of obtaining the naval control of the northern lakes.

It is said that British military and steam naval forces will ascend the St. Lawrence to Lake Ontario; that to counteract these operations we must build an opposition steam-navy at Pittsburg and Memphis, and collect out troops on the Ohio and Mississippi, ascend the Mississippi and Illinois, Lake Michigan, Lake Huron, and the Georgian Bay, cross over to the Ottawa by French river and Lake Nipissing, or Moon river and the Muskago, then