use Philadelphia was the seat of Congress, and was contrary to
sound military policy. The conquest therefore was early lost; but it
was yet more dearly won, for by this diversion of the British forces
the different corps were placed out of mutual support, and the control
of the water-line of the Hudson was abandoned. While Burgoyne, with
seven thousand regular troops, besides auxiliaries, was moving down to
seize the head-waters of the river, fourteen thousand men were removed
from its mouth to the Chesapeake. The eight thousand left in or near
New York were consequently tied to the city by the presence of the
American army in New Jersey. This disastrous step was taken in August;
in October Burgoyne, isolated and hemmed in, surrendered. In the
following May the English evacuated Philadelphia, and after a painful
and perilous march through New Jersey, with Washington's army in close
pursuit, regained New York.

This taking of the British fleet to the head of the Chesapeake,
coupled with the ascent of the Potomac in 1814 by English
sailing-frigates, shows another weak line in the chain of the American
colonies; but it was not, like that of the Hudson and Champlain, a
line both ends of which rested in the enemy's power,--in Canada on the
one hand, on the sea on the other.

As to the sea warfare in general, it is needless to enlarge upon the
fact that the colonists could make no head against the fleets of Great
Britain, and were consequently forced to abandon the sea to them,
resorting only to a cruising warfare, mainly by privateers, for which
their seamanship and enterprise well fitted them, and by which they
did much injury to English commerce. By the end of 1778 the English
naval historian estimates that American privateers had taken nearly a
thousand merchant-ships, valued at nearly L2,000,000; he claims,
however, that the losses of the Americans were heavier. They should
have been; for the English cruisers were both better supported and
individually more powerful, while the extension of American commerce
had come to be the wonder of the statesmen of the mother-country. When
the war broke out, it was as great as that of England herself at the
beginning of the century.

An interesting indication of the number of the seafaring population of
North America at that time is given by the statement in Parliament by
the First Lord of the Admiralty, "that the navy had lost eighteen
thousand of the seamen employed in the last