> > One of the benefits of the "horseless carriage" was the > elimination (sic) > of the problem of horse effluent on the streets. > > While the total amount of pollution from cars and trucks > today may well > exceed that from horses a century ago that's mostly due to the vast > increase in travel. >
That's highly unlikely, even disregarding the fact that the cars enabled the increase in travel. Comparing the total amount like that doesn't really mean anything anyway. Probably the best way to do it would be by comparing the pollution cost of carrying the same loads for the same period of time - eg the capacity of a truck for the lifetime of the truck, against the number of horses required to carry the same capacity for as long. Bearing in mind, of course, that what goes into and comes out of horses is entirely organic, sustainable and recyclable, which is not the case with cars. And also taking into account the pollution costs of producing what goes in, getting it to the consumer (truck or horse), and dealing with what comes out. Bob -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
