For a while they puzzled over the mystery, trying to find some way in which the discovery might be made to serve a practical purpose—all except Herb, who retired to one corner of the “lab” to fuss with some chemicals which he fondly hoped might be used in the construction of a battery.
So engrossed were the boys in the problem of the magnet and vacuum tube that they forgot all about Herb and his experiments. So what happened took them completely off their guard.
There was a sudden cry from Herb, followed closely by an explosion that knocked them off their feet. For a moment they lay there, a bit dazed by the shock. Then they scrambled to their feet and looked about them. Herb, being the nearest to the explosion, had got the worst of it. His face and hands were black and he was shaking a little from the shock. He gazed at the boys sheepishly.
“Wh-what happened?” asked Jimmy dazedly.
“An earthquake, I guess,” replied Bob, as he looked about him to see what damage had been done.
Some doughnuts, which their namesake had recently fetched from the store, lay scattered upon the floor, together with some rather dilapidated-looking pieces of candy, but aside from this, nothing seemed to have been damaged seriously.
Jimmy’s followed Bob’s gaze, and, finding his precious sweets upon the floor, began gathering them up hastily, stuffing a doughnut in his mouth to help him hurry. What mattered it to Jimmy that the floor was none too clean?
“Say, what’s the big idea, anyway,” Joe demanded of the blackened Herb. “Trying to start a Fourth of July celebration, or something?”
“I was just mixing some chemicals, and the result was a flare-up,” explained Herb sulkily. “Now, stop rubbing it into a fellow, will you? You might know I didn’t do it on purpose.”
Bob began to laugh.