“Not a hundred per cent. of hits, evidently,” he muttered.  “Still, one was enough.”

“What is it?” asked MacLeod.

“An incendiary pastille.  On contact, the nose burns away anything it hits, goes right through corrugated iron.  It carries a charge of thermit ignited by this piece of magnesium ribbon.  You know what thermit will penetrate with its thousands of degrees of heat.  Only the nose of this went through the netting and never touched a thing.  This didn’t explode anything, but another one did.  Thousands of gallons of alcohol did the rest.”

Kennedy had picked up his other package as we ran, and was now busily unwrapping it.  I looked about at the crowd that had collected, and saw that there was nothing we could do to help.  Once I caught sight of Gertrude’s face.  She was pale, and seemed eagerly searching for some one.  Then, in the crowd, I lost her.  I turned to MacLeod.  He was plainly overwhelmed.  Kennedy was grimly silent and at work on something he had jammed into the ground.

“Stand back!” he cautioned, as he touched a match to the thing.  With a muffled explosion, something whizzed and shrieked up into the air like a sky-rocket.

Far above, I could now see a thing open out like a parachute, while below it trailed something that might have been the stick of the rocket.  Eagerly Kennedy followed the parachute as the wind wafted it along and it sank slowly to the earth.  When, at last, he recovered it I saw that between the parachute and the stick was fastened a small, peculiar camera.

“A Scheimpflug multiple camera,” he explained as he seized it almost ravenously.  “Is there a place in town where I can get the films in this developed quickly?”

MacLeod, himself excited now, hurried us from the scene of the explosion to a local drug-store, which combined most of the functions of a general store, even being able to improvise a dark-room in which Kennedy could work.

It was some time after the excitement over the explosion had quieted down that MacLeod and I, standing impatiently before the drug-store, saw Snedden wildly tearing down the street in his car.  He saw us and pulled up at the curb with a jerk.

“Where’s Gertrude?” he shouted, wildly.  “Has any one seen my daughter?”

Breathlessly he explained that he had been out, had returned to find his house deserted, Gertrude gone, his wife gone, even Jackson’s car gone from the barn.  He had been to the works.  Neither Garretson nor Jackson had been seen since the excitement of the explosion, they told him.  Garretson’s racer was gone, too.  There seemed to have been a sort of family explosion, also.

Kennedy had heard the loud talking and had left his work to the druggist to carry on and joined us.  There was no concealment now of our connection with MacLeod, for it was to him that every one in town came when in trouble.

In almost no time, so accurately did he keep his fingers on the fevered pulse of Nitropolis, MacLeod had found out that Gertrude had been seen driving away from the company’s grounds with some one in Garretson’s car, probably Garretson himself.  Jackson had been seen hurrying down the street.  Some one else had seen Ida Snedden in Jackson’s car, alone.