k,
American citizens murdered and the United States Government defied when
the German navy has been employing the man who murdered the passengers
of the _Lusitania_ as the chief instructor of submarine murderers?

The Krupp interests have played a leading role in the war, not only by
manufacturing billions of shells and cannon, and by financing
propaganda in the United States, but by building submarines. At the
Krupp wharves at Kiel some of the best undersea craft are launched.
Other shipyards at Bremen, Hamburg and Danzig have been mobilised for
this work, too. Just a few weeks before diplomatic relations were
broken a group of American doctors, who were investigating prison camp
conditions, went to Danzig. Here they learned that the twelve wharves
there were building between 45 and 50 submarines annually. These were
the smaller type for use in the English Channel. At Hamburg the
Hamburg-American Line wharves were mobilised for submarine construction
also. At the time diplomatic relations were severed observers in
Germany estimated that 250 submarines were being launched annually and
that preparations were being made greatly to increase this number.

Submarine warfare is a very exact and difficult science. Besides the
skilled captain, competent first officers, wireless operators and
artillerymen, engineers are needed. Each man, too, must be a "seadog."
Some of the smaller submarines toss like tubs when they reach the ocean
and only toughened seamen can stand the "wear and tear." Hence the
weeks and months which are necessary to put the men in order before
they leave home for their first excursion in sea murder.

But Germany has learned a great deal during two years of hit-and-miss
submarine campaigns. When von Tirpitz began, in 1915, he ordered his
men to work off the coasts of England. Then so many submarines were
lost it became a dangerous and expensive military operation. The
Allies began to use great steel nets, both as traps and as protection
to warships. The German navy learned this within a very short time,
and the military engineers were ordered to perfect a torpedo which
would go through a steel net. The first invention was a torpedo with
knives on the nose. When the nose hit the net there was a minor
explosion. The knives were sent through the net, permitting the
torpedo to continue on its way. Then the Allies doubled the nets, and
two sets of knives were attached to the German torpedoes.