“Astern” of this wonderful invention was a rudder of vulcanized silk and vanadium steel framework, which, when the invention was in use as a land vehicle, was folded. When it was desired to take the air the release of a simple clutch caused the rudder to assume its proper position. At the same time, two long planes could be attached to the sides of the car, to be used in ascending or descending. The machine had two steering and governing devices. One wheel was used for the auto control, and another “tiller” was put in use when it was soaring through the air. The control of the aerial rudder, planes and engine, all centered in this second wheel, thus putting the craft, at all times, under one man—or boy—management. In conclusion, it may be mentioned that the craft was equipped with speedometer, barometer, barograph and patent self-starting devices, doing away with the old-fashioned “cranking” of the engine. The wheels were fitted with semi-solid tires of great size and strength, and the shock-absorbers before mentioned obviated any danger of a severe jar or jounce on landing. The machine had been given several trials at High Towers and had been found to work perfectly. It is not necessary here to give a description of the loading of the aero-auto, the leave takings, and the final instructions and messages that passed between the _Vagrant_ and the _Sea King_. Suffice it to say, that at eight o’clock that morning all preparations on both sides were completed and that at eight-ten precisely the two vessels parted company. The _Sea King_ steamed northward slowly, bound for Lone Island, and the _Vagrant_ headed for the mouth of the river on which the plantations of the rascally Mexican were situated. At that time the _Tarantula_ had drifted out of the adventurers’ ken altogether, over the eastern horizon. Leaving Captain Andrews and Jupe in charge of the _Vagrant_, the lads, thoroughly exhausted now that the strain and care of the long night were over, sought their bunks and were soon wrapped in slumber. In their dreams they flew high above the plateaus and rugged ranges of the mysterious land for which they were bound, questing the unknown in search of the lost ones. CHAPTER XII—HERRERA IS NOT CAUGHT NAPPING It was noon of the next day when Captain Andrews announced that they were still some two hundred miles from their destination. But, as the boys were all three of them busy over the aero-auto, adjusting and examining every part of the queer craft, the time flew swiftly. The dawn of the third day found them anchored off the jungle-clad coast, while not a mile from them the waves were breaking on the bar that marked the mouth of the shallow river, which, they subsequently learned, was called the Apak.