In fact, ISTR that a key part of old stories is folks accidentally trampled by horses. That doesn't say anything about which is worse: horses or cars. I wonde

In fact, ISTR that a key part of old stories is folks accidentally trampled by horses. That doesn't say anything about which is worse: horses or cars. I wonder if any study has been done about that. It'd have to be complex, e.g. covering sicknesses from manure, sicknesses from leaded gasoline, sicknesses from pollution &c.