“When I became chief of intelligence I found that an underground wire had been laid to the castle from the Eighth Division headquarters, which will be our general staff headquarters in time of war,” he said.  “The purpose was the same as now, but abandoned as chimerical.  All that was necessary was to install the instrument, which Feller did.  I, too, saw the plan as chimerical, yet it was a chance—­the one out of a thousand.  If it should happen to succeed we should play with our cards concealed and theirs on the table.”

“The noble art of war, so sportsmanlike!” she exclaimed.  “So like the rules and ideals of the Olympic games!  But the games will not serve to keep nations virile.  They must shed blood!”

“Sportsmanlike?  Not in the least!” he said.  “The sport and glamour of war are past.  The army becomes a business, a trade that ought to be uniformed in blue jumpers rather than gold lace.  We are in an era of enormous forces, untried tactics, and rapidly changing conditions.  This is why the big nations hesitate to make war; why they prepare well; why the stake is so great that the smallest detail must not be overlooked.”

She could not hold back her arguments, reason was so unquestionably on her side.

“Yes, the cunning of the fox, the brutality of Cain, using modern science and invention!  Feint and draw your enemy into a cul-de-sac; screen your flank attacks; mask your batteries and hold their fire till the infantry charge is ripe for decimation!  Oh, I have been brought up among soldiers!  I know!”

“The rest of Feller’s part you have guessed already,” he concluded.  “You can see how a deaf, inoffensive old gardener would hardly seem to know a Gray soldier from a Brown; how it might no more occur to Westerling to send him away than the family dog or cat; how he might retain his quarters in the tower; how he could judge the atmosphere of the staff, whether elated or depressed, pick up scraps of conversation, and, as a trained officer, know the value of what he heard and report it over the ’phone to Partow’s headquarters.”

“But what about the aeroplanes?” she asked.  “I thought you were to depend on them for scouting.”

“We shall use them, but they are the least tried of all the new resources,” he said.  “A Gray aeroplane may cut a Brown aeroplane down before it returns with the news we want.  At most, when the aviator may descend low enough for accurate observation he can see only what is actually being done.  Feller would know Westerling’s plans before they were even in the first steps of execution.  This”—­playing the thought happily—­“this would be the ideal arrangement, while our planes and dirigibles were kept over our lines to strike down theirs.  And, Marta, that is all,” he concluded.  “I’ve tried to make everything clear.”

“You have, quite!” Marta replied decisively.  “Now it is my turn to talk.”

“You have been talking a little already!” he intimated good-naturedly.