Napoleon's Nightingale

Teacher - Your step system confuses me..what exactly would the Egyptians have used to push down the lever to lift a 2.5 ton block of stone? What would the rollars me made of that could support the weight of 2.5 ton stone? Wouldn't the stone flip over the step thereby crushing the slaves on the side pulling the stone? I imagine the system would work on a small scale and low height but not on a large scale with a large height. The pyramid is too high for the step system to work because the Egyptians would have to have built some sort of scafalding capable of holding the weight of the 2.5 ton stone, and lifted the stone onto the scafalding vertically to achieve that height with your step system.