Re: A hypothetical question

Ah . . .  but Gentlemen -

Don't forget the impurities in that "only 45-85% carbon" bituminous coal, some of which are producing the unique "perfume" associated with the burning of coal and, OTOH, the nasty additives mixed into gasoline in lieu of the tetraethyl lead of the "olden days" to smooth the combustion and prevent 'knocking'.  Another downside of burning gasoline in automobile engines is that it's done under significant pressure along with plain old air – which is roughly 80% nitrogen – and thus yields a significant amount of really nasty oxides of nitrogen in the exhaust which gives us the lovely brownish tint of smog, and of course acid rain when these mix with water to produce nitrous and nitric acid.  There's no compression in the firebox of a steam locomotive, so very little – if any – oxides of nitrogen are produced.  Of course compression is even higher in a diseasel than in a gasoline engine, so the oxides of nitrogen problem is even worse.  OTOH, burning coal produces a LOT more soot than a gas engine or even a diseasel — as the residunces of Durango will gladly remind us . . .

- Sincerely, Willie  (Wm. Claude Johnson-Barr III, Esq.)  
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