Fear of Strong Steam

At the beginning of the eighteenth century Newcomen successfully developed a ‘fire’ engine that exploited atmospheric pressure to do work. The cylinder of the engine was filled with steam after which cold water was let in condensing the steam. This formed a partial vacuum and atmospheric pressure forced the piston down, thereby performing work. In the latter half of the eighteenth century James Watt carried out a large amount of development work on the engine; including the introduction of a separate condenser, which improved thermal efficiency. However, Watt refused to use what he called ‘strong’, high-pressure, steam. He believed strong steam to be far too dangerous, on a par with gunpowder.

Watt was right: not only was strong steam dangerous, it was unnatural. By unnatural I mean that it exceeded, in a fundamental way, the capacity of the forces of nature. His engines were a part of the natural order in that they employed only atmospheric pressure. That is, they were in the same category as windmills and waterwheels. For going beyond what nature intended, for a craft-based society not long out of the medieval mindset and that had yet to systematise science, was fraught with danger. Watt, however brilliant an engineer, was determined to frustrate this ungodly enterprise, and did so through the patents he controlled.

For a quarter of a century, he delayed the deployment of strong steam until, around 1800, the dyslexic Cornish engineer Trevithick successfully built a high-pressure steam engine. Within twenty-five years the Stockton and Darlington railway was running. Another twenty-five years after that came the Great Exhibition. In that half-century, the foundations of our technological society were laid. The powerhouse of change was a small but powerful strong-steam engine. Watt’s trepidation vindicated, nothing was ever the same again?