But first must come business; they must go over the machine very carefully and see if the long, hard run from Panama had done any damage; and they must replenish their fuel, oil, and water supply. They were happy to find both engines in fine shape, thanks to the possibility of alternating them in transit, and beyond a number of scratches and the cracked glass made by the condors in their attack in crossing the Andes the airplane was in perfect shape.  Paul climbed up and examined the helium-gas valves, of which there were three in each wing, one for each of three compartments, and announced that the pressure showed only an insignificant decrease.  At the rate of escapage indicated, they would have plenty to last them for the whole trip.  This was reassuring knowledge, for no envelope can be made so impervious that light gases will not escape at all.  The body compartment also showed good pressure.