loon. To tell the truth he much preferred aeroplanes to balloons, but he realized that in a country where the jungle growth prevailed, and where there might be no level places to get a "take off," or a starting place for an aeroplane, the balloon was more feasible.
But he need have had no fears, for the balloon worked perfectly. In the bag Tom used a new gas, much more powerful even than hydrogen, and which he could make from chemicals that could easily be carried on their trip.
The air craft was small but powerful, and could easily carry Tom, Ned and Mr. Damon, together with a quantity of food and other supplies. They intended to use it by starting from the place where they would leave the most of their baggage, after getting as near to the city of gold as they could by foot trails. Tom hoped to establish a camp in the interior of Mexico, and make trips off in different directions to search for the mined temple. If unsuccessful they could sail back each night, and, if he should discover the entrance to the buried city there was food enough in the car of the balloon to enable them to stay away from camp for a week or more.
In order to give the balloon a good test, Tom took up with him not only Ned and Mr. Damon, but Eradicate and Mr. Swift to equalize the
