69 39 34 amp 70 39 34 and the tube 36 39 34 form a sealed container with the tube 36 39 34 providing communication between the tanks 69 39 34 amp 70 39 34 the power source 30 39 34 also comprises a means of facilitating movement of the container such as a means comprising a flexible member such as a drive cable 72 39 34 and one or more movable members such as two pulleys 34 39 34 amp 35 39 34 supported by a stand 68 39 34 each end of the drive cable 72 39 34 is attached to a different tank 69 39 34 or 70 39 34 and the drive cable 72 39 34 is positioned on the pulleys 34 39 34 amp 35 39 34 which support the drive cable 72 39 34 which supports the tanks 69 39 34 amp 70 39 34 the drive cable 72 39 34 can be moved back and forth over the pulleys 34 39 34 amp 35 39 34 as the tanks 69 39 34 amp 70 39 34 alternate being at a higher altitude this power source 30 39 34 has two original positions one of which is shown by the solid lines in fig7 the other original position is the position at which the.