Re: Can a man hammer with a 1 lb stone to exert a force of 20,000 psi?

Dear David

Mammoth bones are obviously suited for carrying very heavy loads. I assume 
that the 20,000 psi that you mentioned refer to a fully intact bone. 
However, if the bone was scratched in the first place the force needed for 
fracture would be considerable reduced. 

I hope this comment is helpful to you.

U. Dammer

PS. Even coming from a "metric country", I think that psi is the unit for a 
pressure (or stress), rather than simply for forces.