Then a swish in the wheat, a soft thud, very low, unmistakably came to Kurt’s ear.  He listened, turning his ear to the wind.  Presently he heard it again—­a sound relating both to wheat and earth.  In a hot flash he divined that some one had thrown fairly heavy bodies into the wheat-fields.  Phosphorus cakes!  Kurt held his breath while he peered down the gloomy road, his heart pounding, his hands gripping the rifle.  And when he descried a dim form stealthily coming toward him he yelled, “Halt!”

Instantly the form wavered, moved swiftly, with quick pad of footfalls.  Kurt shot once—­twice—­three times—­and aimed as best he could to hit.  The form either fell or went on out of sight in the gloom.  Kurt answered the excited shouts of his men, calling them to come across to him.  Then he went cautiously down the road, peering on the ground for a dark form.  But he failed to find it, and presently had to admit that in the dark his aim had been poor.  Bill came out to relieve Kurt, and together they went up and down the road for a mile without any glimpse of a skulking form.  It was almost daylight when Kurt went home to get a few hours’ sleep.

CHAPTER XII

Next day was one of the rare, blistering-hot days with a furnace wind that roared over the wheat-fields.  The sky was steely and the sun like copper.  It was a day which would bring the wheat to a head.

At breakfast Jerry reported that fresh auto tracks had been made on the road during the night; and that dust and wheat all around the great field showed a fresh tramping.

Kurt believed a deliberate and particular attempt had been made to insure the destruction of the Dorn wheat-field.  And he ordered all hands out to search for the dangerous little cakes of phosphorus.

It was difficult to find them.  The wheat was almost as high as a man’s head and very thick.  To force a way through it without tramping it down took care and time.  Besides, the soil was soft, and the agents who had perpetrated this vile scheme had perfectly matched the color.  Kurt almost stepped on one of the cakes before he saw it.  His men were very slow in finding any.  But Kurt’s father seemed to walk fatally right to them, for in a short hundred yards he found three.  They caused a profound change in this gloomy man.  Not a word did he utter, but he became animated by a tremendous energy.

The search was discouraging.  It was like hunting for dynamite bombs that might explode at any moment.  All Kurt’s dread of calamity returned fourfold.  The intense heat of the day, that would ripen the wheat to bursting, would likewise sooner or later ignite the cakes of phosphorus.  And when Jerry found a cake far inside the field, away from the road, showing that powerful had been the arm that had thrown it there, and how impossible it would be to make a thorough search, Kurt almost succumbed to discouragement.  Still, he kept up a frenzied hunting and inspired the laborers to do likewise.