For some further account of the three chums, we must refer our readers to the first volume of this series, The Motor Rangers’ Lost Mine. This related how Nat, the son of a poor widow, unexpectedly came into his own and from an employé’s position was raised to one of comparative affluence. For a holiday tour when they returned from Lower California, where Nat by accident had located his mine, the chums took an eventful trip through the Sierras. What befell them there, and how they combated unscrupulous enemies and had lots of jolly fun, was all set forth in the second volume devoted to their doings, The Motor Rangers Through the Sierras. Some sapphires found by them on this trip led to a strange series of incidents and adventures attendant on their efforts to restore them to their rightful owner. The precious stones were stolen, recovered, and lost again, only to be delivered safely at last. These exciting times, passed by the lads on their cruiser, the _Nomad_, which took them half across the Pacific, were described in the third volume of the young rangers’ doings, The Motor Rangers on Blue Water. Their voyage in Professor Grigg’s wonderful air-ship, the _Discoverer_, has been already referred to. With this necessarily brief introduction to the young campers, let us return to Goat Island.
Directly Ding-dong reached the hut housing the apparatus, he flung himself down before the instruments and hastily jammed the head-piece, with its double “watch-case” receivers, over his ears. He picked up a pencil and placing it conveniently above a pad of paper that was always kept affixed to the table holding the sending and receiving appliances, he began to send a storm of dots and dashes winging out in reply to the wireless impulse that had set the gong sounding.
“_This is Goat Island!_” he banged out on the key, while the spark leaped and writhed in a “serpent” of steel-blue flame between the sparking points. It whined and squealed like an animal in pain as Ding-dong’s trembling fingers alternately depressed and released the “brass.”
“_Goat Island! Goat Island! Goat Island!_” he repeated monotonously, and then switched the current from the sending to the receiving instruments.