The Japanese, of course, in their war with Russia in Manchuria made
extensive use of spies, and Port Arthur, with all its defects of
fortification and equipment, was known thoroughly inside and out to
the Japanese general staff before they ever fired a shot at it.

In the field service regulations of the German army a paragraph
directed that the service of protection in the field--that is to
say, outposts, advanced guards, and reconnaissances--should always be
assisted by a system of spying, and although this paragraph no longer
stands in the book, the spirit of it is none the less carried out.

The field spies are a recognised and efficient arm.

Frederick the Great is recorded to have said: "When Marshal Subise
goes to war, he is followed by a hundred cooks, but when I take the
field I am preceded by a hundred spies."

The present leader of the German army might well say the same, though
probably his "hundred" would amount to thousands.

We hear of them dressed in plain clothes as peasants, and signalling
with coloured lights, with puffs of smoke from chimneys, and by using
the church clock hands as semaphores.

Very frequently a priest was arrested and found to be a spy disguised,
and as such he was shot. Also a German chauffeur in a French uniform,
who had for some time been driving French staff officers about, was
found to be a spy, and so met his death.