I didn't think such things existed anymore...

I've just seen a rag and bone man! I was thinking only the other day about how weird it was that now we're all recycling mad it was a shame they didn't exist still and lo and behold they do. Not quite Steptoe & Son, it was a flat bed truck rather than a horse and cart, but they were driving along shouting 'rag'n'bone' just like in that Playschool 'through the window' film. I was going to say that the horse would have been 'greener' but I read an article the other day by the vegetarian society about how wasteful it was feeding animals and how much methane and CO2 they produce so I don't know if it would have been. If you ran the truck (which seemed to be diesel from the sound) on rape seed oil (which I don't for a moment think they were) maybe it would be better than the horse? Are modern diesel engines more efficient than mammalian metabolism?