That problem fled through a mass of gears and cams; and the partial solution, the sum of the two earthling's life expectancies divided by that of the priest Klaggchallak, ran across a shaft to the third stage, which would determine the old priest's value to the society of Mars. On into the fourth stage the problem flowed, to combine all previous factors with the earthlings' social value to Mars, a negative number. In a few moments the problem had progressed to the fifth stage of the Machine, where the first steps of the 'finagle factor' were solved. The product, a negative number as could be seen by the reversed rotation of the main shaft, bowed into the sixth stage, which was to extract square root. * * * * * The turbine howled protest as it was forced to overcome the inertia of the sixth stage; but a governor at the input stage held the shaft-speed constant. The seventh stage, all ready for the problem when it should appear from the sixth, held all the computations of the first four stages in its smoothly-turning entrails. The initial portion of the sixth stage began to move slowly. There was a sudden, grating noise as the feed-in gear of the fifth stage came in contact with a solution gear of the sixth which refused to move. The whine of the mercury-turbine engine was shaking the ground beneath the two officers' feet now. As the Martian technicians and picnickers looked on in amazement, the shaft between the fifth stage and the sixth began to twist like a stick of moist putty. The sixth stage strained and shuddered, then followed the twisting shaft over, tearing its moorings from the ground and smashing upside-down. The seventh stage entered into the chaos, ripping out anchors of steel-in-concrete and slamming onto its side. In a moment all the machines in the bowl were muttering and straining against the earth. Rhinklav'n ran to the stairway that led down into the pit. In the adobe powerhouse the mercury engine was whirling at twenty times its optimum rate, tearing the atmosphere with the sound of its screaming power. There was the rattle of shrapnel exploding within the walls of the powerhouse as the turbine threw off the restrainment of its governor. The whole field within the bowl was a mass of twitching clockwork, shaken by the final stormings of the suicidal turbine. Bars of shining steel twisted and snapped, gear teeth flew singing through the thin air. The final chain of stages tore itself loose from anchoring and crashed to its side. There was a final roar of defiance from the turbine, and the powerhouse walls dissolved before an out-rushing blast of superheated mercury. Kim and Barnaby threw themselves to the ground as the din increased for a moment, and the Martian sightseers sought refuge behind nearby buildings. Suddenly, the Machine was silent, except for the tinkle of scraps of metal falling to the cement.