e of operations against Canada;
and that it is indispensable to success in war that this line be well
fortified in time of peace. All agree that the St. Lawrence above
Quebec constitutes the _key_ point of the enemy's defence, and the
_objective_ point towards which all our operations should be directed.
To reach this point, all our Boards of Engineers have deemed it best to
collect our troops at Albany and advance by Lake Champlain, a distance
of only two hundred miles. Besides the advantages of a good water
communication the whole distance for the transportation of military
stores, there are several roads on each side, all concentrating on this
line within our own territory. It has already been shown by the brief
sketch of our northern wars, that this line has been the field of strife
and blood for _fifteen campaigns_. Nature has marked it out as our
shortest and easiest line of intercourse with Canada, both in peace and
war. Military diversions will always be made on the eastern and western
extremities of this frontier, and important secondary or auxiliary
operations be carried on by the eastern and western routes; but until we
overthrow the whole system of military science as established by the
Romans, revived by Frederick and practised and improved by Napoleon, the
_central and interior line_, under all ordinary circumstances, will
furnish the greatest probabilities of success.

If the line of Lake Champlain is, as we have endeavored to show, the
most important line in the north; its security by fortifications is a
matter of the greatest interest. The works recommended by the Board,
consist of a single fort, costing $600,000, at Rouse's Point, on the
extreme frontier, and unfortified depots at Plattsburg and Albany. But
is this sufficient to accomplish the object? If the hostile army should
pass the extreme frontier barrier, what is to retard his advance,--what
defensive works are to protect the debouche of the Northern canal, or
even to save the great central depot? We know of no foreign engineer who
has recommended less than _three_ lines of fortifications for the
security of a land frontier; and Napoleon, the Archduke Charles, and
General Jomini, agree in recommending at least this number of lines.
There may be circumstances that render it unnecessary to resort to a
three-fold defence throughout the whole extent of our northern frontier;
but upon our main line of communication with Canada,--a line of maximum
imp