Uriel's Machine (More comet discourse)

I'm reading Uriel's Machine -- pretty interesting. Using recorded observations gathered over a number of years (which was a tedious process due to Britain's habitually overcast sky), the authors built a case supporting the possibility that some of the megalithic sites such as Newgrange were astronomical observatories.

I can't imagine what kind of effort must have gone into constructing one of these sites, though. What a horrible life, spent quarrying horrendously large stones out of somewhere, chipping away at solid rock foundation acreage with stone tools to fit the stones into, and then hauling zillion-pound boulders uphill and standing them upright, and then putting the top on them... somehow. For a while (as evidenced by the megaliths and the pyramids etc.), people were obsessed with LARGE and it was more important to get those things built than to live.

Theory has it that in the aftershock of a major catastrophe (such as a comet strike), the reaction was to create structures that could withstand anything and predict events years in advance.

So, wellp, hum.