The Order Book
Six engagements, 1712 to 1908, taken in strict rotation.
No. I — The Flooded Level (A.D. 1715)
The adventurers of Wheal Fortune, Cornwall
The twenty-six fathom level stands drowned and the tinners idle. Coal comes round the Land’s End by sea and every bushel of it is begrudged. The adventurers will have the water out, but they will not be ruined raising it: mind the injection, for that is where an atmospheric engine is won or lost.
No. II — The Albion Mill (A.D. 1786)
The Albion Flour Company, Blackfriars, London
A flour mill in the middle of London, worked by fire instead of wind — half the city says it cannot be done and the other half that it should not. The stones want smooth, steady turning and the company’s coal is weighed at the gate. Their letter is blunt: the engine of Mr. Watt is dear, and must earn its price in coal spared. Watch the safety valve: every wisp that blows off is coal the company paid for and no flour ground by it — yet starve the fire and the stones fall behind the contract.
No. III — An Engine to Travel (A.D. 1804)
Capt. Richard Trevithick, for the Penydarren wager
The Captain has wagered five hundred guineas that steam will haul iron down the Penydarren tramroad, and the whole engine must ride the rails it works. No condenser, no great beam, no acre of engine-house: a cylinder you could carry and strong steam to make up for it. Raise the pressure and give the little cylinder its full stroke of steam — a cylinder this small cannot afford the fine economies of the great mills. And leave the safety valve alone, whatever the Captain himself was known to do.
No. IV — The Spinning Contract (A.D. 1855)
The Ock Street Cotton Mill, Massachusetts
Eleven hundred spindles, and thread that snaps if the shafting so much as sighs. Mr. Corliss offers his engine on his usual astonishing terms: no price at all, only the value of five years’ coal saved against the mill’s old engine. The trip gear holds the speed; your business is the fire. Stoke to the work, not past it — every pound of surplus steam blows off the valve as pure loss.
No. V — The City Waterworks (A.D. 1878)
The Metropolitan Water Board
A city’s worth of drinking water to be lifted every hour of every day, for ever. At that scale nothing matters but the coal bill, and the Board’s inspector reads the meter weekly. Two cylinders, one push: proportion the great low-pressure cylinder to its receiver, cut off early in the high, and let the steam spend itself twice over before the condenser takes it.
No. VI — The Electric Light Company (A.D. 1910)
The Borough Electric Light & Power Co.
Dynamos, and a town that notices every flicker. The Company wants high, steady revolutions and an engine-room coal bill the turbine men cannot laugh at. One cylinder, steam one way only: keep the cutoff short, keep the condenser on — a uniflow traps its own exhaust against the piston without one — and hold a hundred and ten revolutions as though the lamps depended on it, because they do.