dly developed into the most powerful navy the world had ever
seen, the United States Government from the very beginning of the
war locked the Confederate States in a wall of iron. None might pass
going in or out, except by stealth and at the peril of property and
life. Outside the harbour of every seaport in the control of the
Confederates the blockading men-of-war lurked awaiting the blockade
runners. Their vigilance was often eluded, of course, yet
nevertheless the number of cargoes that slipped through was
painfully inadequate to meet the needs of the fenced-in States.
Clothing, medicines, articles of necessary household use were denied
to civilians. Cannon, rifles, saltpetre, and other munitions of war
were withheld from the Confederate armies. While the ports of the
North were bustling with foreign trade, grass grew on the
cobble-stoned streets along the waterfronts of Charleston and
Savannah. Slow starvation aided the constant pounding of the
Northern armies in reducing the South to subjection.

Had the Confederacy possessed but a few submarines of modern type
this situation could not have persisted. Then, as to-day, neutral
nations were eager to trade with both belligerents. There were then
more neutrals whose interests would have compelled the observance of
the laws of blockade, which in the present war are flagrantly
violated by all belligerents with impunity. A submarine raid which
would have sunk or driven away the blockading fleet at the entrance
to a single harbour would have resulted in opening that harbour to
the unrestricted uses of neutral ships until the blockade could be
re-established and formal notice given to all powers--a formality
which in those days, prior to the existence of cables, would have
entailed weeks, perhaps months, of delay.

How serious such an interruption to the blockade was then considered
was shown by the trepidation of the Union naval authorities over the
first victories of the _Merrimac_ prior to the providential arrival
of the _Monitor_ in Hampton Roads. It was then thought that the
Confederate ram would go straight to Wilmington, Charleston, and
Savannah, destroy or drive away the blockaders, and open the
Confederacy to the trade of the world.

Even then men dreamed of submarines, as indeed they have since the
days of the American Revolution. Of the slow development of that
engine of war to its present effectiveness we shall speak more fully
in later chapters. Enough now