"No; there are two stabilizers, as you will see,--here, and here," was Paul's response, pointing his finger to the parts.  "But, as each one is exactly like the other in its construction, only the one has been drawn in detail.  The other stabilizer runs lengthwise of the cockpit and takes care of the elevator.  Both of these are operated by compressed air, which proceeds from a little tank, right here.  The tank is kept supplied by two tubes which lead into it, and each of which joins a small pump operated by a fan which is right here on each side of the fuselage where the onrush of wind will keep it humming as the airplane travels.