Excerpts & Engines



Online short stories: Voice of Steel Click here for story Electrisarian Click here for story Unthinkable Click here for story Online excerpts From Novels Voidfarer (Tor, Feb. 2006) Click here for excerpt
	Engines... There is nothing quite like having a model around to get the feeling of the vessel you are on, be it a steamship, a sailing ship or spaceships. Sean often builds models to make sure his engines and inventions actually work. . THE SPIRAL BRIAR required a steam engine that could be built using medieval technology. Medieval folk did have a steam boiler called a sufflator, which acted as a bellows for furnaces, so I could use this as a source of steam pressure. My innovation was to use water as the piston, removing the need for high-precision machining. I tested a very rough mockup in the bathtub. It was not a pretty sight, but it worked. I then built the model pictured here, to get a feeling for the ship's layout while writing the story. Now I am using it for the same purpose while writing the novel. Some time later I discussed the idea with marine engineer Jetse de Vries, and while pointing out that it would be pretty inefficient, he conceded that it would work. Its closest relative in real history is Thomas Savery's steam pump of 1698. STEAMPUNK SCANDAL: It is a curious but lamentable fact that most people who write steampunk do not have their own steam engine. What is the world coming to? Just for the record, this rather cute little gothic number is mine, and it gets fired up for the occasional visitor who asks "Does it work?" Some time after VOYAGE OF THE SHADOWMOON had been published, I was mortified to discover that my imaginary wind-powered submarine was not original. In 1773 an English waggon maker named Day had made some modifications to a sloop of about the same size as the Shadowmoon, then submerged it in a river with himself aboard. He later resurfaced successfully with his vessel. The second test was in deeper water, but was not quite so successful. A large eruption of bubbles was observed soon after his craft submerged, and he was never seen again. I made the model in this picture just to get a feel for the layout of the Shadowmoon while I was writing the novel, so unfortunately it does not work. I did make a much less attractive working version from a baking tin, half a plastic bottle, some wire and some roofing lead. THE DECIAD was the short story that won the 1985 Worldcon's writing competition, and was published the following year in Omega. Expanded into the novel-length THE CENTURION's EMPIRE, it became my first book to sell in the US. This is a model of the Roman warship that figured rather prominently.
In VOICE OF STEEL I had to describe an interstellar spacecraft built in London around 1420. That was obviously a challenge. I decided that a wooden frame, a couple of large barrels for the living quarters and control cabin, some control chains and wheels, a static electricity generator, and some other steampunkish touches would have the right style. I made the mistake of lending the model to someone, and it was subsequently lost. This photograph of it is the only one that I took. . In TOWER OF WINGS an important premise is that a medieval siege engine called a trebuchet can be used to launch a medieval hang glider (yes, there were medieval hang gliders, some even flew, and a few pilots even survived the landings). I built a model trebuchet and tested it, then built a glider of vaguely bird-like shape. The trebuchet launched the little glider on a ten toot flight across the living room on the very first attempt, proving the concept. Later, while demonstrating the trebuchet to Peter McNamara at a dinner party, I managed to break a champagne glass with an olive at thirty feet. Peter was very impressed, but the owner of the glass was not. Some people just don't appreciate art The Calculor from SOULS IN THE GREAT MACHINE never existed as a model that you can touch or look at, but I certainly did test it as a computer program. For those of you who are into archeology, I wrote it in Pascal and ran it on a Vax 11/780 emulating a PDP 11. I wrote the program to model 32 humans with abacus frames in two 16-human, self-checking processors. I had to make up an operating system and programming language, and I built in delays to slow it down to simulate human components. After running a couple of simple programs on it, I stored it on a tape. I then stored the tape in a ceiling. A few hot summers came and went. When I tried to play it back, it self-destructed. Earlier I had decided that the 8,000 or so words that detailed the Calculor's operating system and programming language were slowing down the novel's action, so I cut nearly all of that out. Thus no code or specs for the Calculor have survived. Ever since then I have been dodging flack from computer-literate fans who want to write and run their own model of the Calculor. One of these days, in my copious free time, I should try to reconstruct the original. THE COLOURS OF THE MASTERS featured a recording-only sound system from the 1820s. This concept sketch of the harmonoscribe was probably done late in 1986, when I was writing the story. I remember that I was working back late one night, and waiting for a program to compile. I got the idea from Scott de Martinville's 1857 phonautograph, a device which could record sound on a soot-coated glass disk or (later) paper, but not play it back. Reality later caught up with SF when an American team managed to play back the Scott de Martinville recordings two decades after my story was published.