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I believe that Charles T. Porter's “Engineering Reminiscences“ was a gift from my grandfather, who was himself a machinist. Porter's most prominent contribution was the high-speed steam engine, that is to say, a steam engine operating at more than about 100 RPM. Although steam engines and their governors proved to be somewhat of a dead end, some of his dynamic balancing techniques are still in use.

Technology changes, people and organizations not so much. Chapter XVII starting on page 189 describes a demonstration of two of his new high-speed steam engines (on operating at 150 RPM the other at 300 RPM) along with one of his colleague's new boilers at the 1870 Fair of the American Institute in New York. The boiler ran slanted water tubes through the firebox to more efficiently separate steam from the remaining water. The engines were small by 1870s standards, one having 16-inch diameter cylinders with a 30-inch stroke and the other having 6-inch diameter cylinders with a 12-inch stroke.

Other exhibitors also had boilers and steam engines, and yet other exhibitors had equipment driven by steam engines. All the boilers and steam engines where connected, but given that steam engines were, then as now, considered to be way cooler than mere boilers, it should not be too surprising that the boilers could not produce enough steam to keep all the engines running. In fact, by the end of the day, the steam pressure had dropped by half, resulting in great consternation and annoyance all around. The finger of suspicion quickly pointed at Porter's two high-speed steam engines—after all, great speed clearly must imply equally great consumption of steam, right?

Porter had anticipated this situation, and had therefore installed a shutoff valve that isolated the boiler and his two high-speed steam engines from the rest of the Fair's equipment. Porter therefore closed his valve, with the result that the steam pressure within his little steam network immediately rose to 70 PSI and the pressure to the rest of the network dropped to 25 PSI. In fact, the boiler generated excess steam even at 70 PSI, so that the fireman had to leave the firebox door slightly open to artificially lower the boiler temperature.

The steam pressure to the rest of the fair continued to decrease until it was but 15 PSI. Over the noon hour, an additional boiler was installed, which brought the pressure up to 70 PSI. Restarting the steam engines of course reduced the pressure, but at 5PM it was still 25 PSI.

The superintendent of the machinery department had repeatedly asked Porter to reopen the valve, but each time Porter had refused. At 5PM, the superintendent made it clear that his request was now a demand, and that if Porter would not open the valve, the superintendent would open it for him. Porter finally agreed to open the valve, but only on the condition that the other managers of the institute verify that the boiler was in fact generating more than enough steam for both engines. These managers were summoned forthwith, and they agreed that the boiler had been producing most of the show's steam and that the pair of high-speed steam engines had been consuming very little. Porter opened the valve, and there was no further trouble with low-pressure steam.

It is all too easy to imagine a roughly similar story unfolding in today's world. ;–)

Porter went on to develop steam engines capable of running well in excess of 1,000 RPM, with one key challenge being convincing onlookers that the motion-blurred engine really was running that fast.

Interestingly enough, steam engines were Porter's third career. He was a lawyer for several years, but became disgusted with legal practice. At about that same time, he became quite interested in the problem of facing stone, that is, producing a machine that would take a rough-cut stone and give it a smooth planar face (smooth by the standards of the mid-1800s, anyway). After a couple of years of experimentation, he produced a steam-powered machine that efficiently faced stone. Unfortunately, at about that same time, others realized that saws could even more efficiently face stone, so his invention was what we might now call a technical success and a business failure.

Oddly enough, we have recently learned that the application of saws to stone was not an invention of the mid-1800s, but rather a re-invention of a technique used heavily in the ancient Roman Empire, and suspected of having been used as early as the 13th century BC. This is one of many interesting nuggets on life in the Roman Empire brought out by the historical novel “Tears of Stone” by Vannoy and Zeiglar. This novel is informed by Zeigler's application of Cold War remote-sensing technology to interesting areas of the Italian landscape, a fact that I had the privilege of learning directly from Zeigler himself.

On the other hand, perhaps Porter's ghost can console himself with the fact that the earliest stone saws were hand-powered, and those of the Roman Empire were water powered. Porter's stone-facing machine was instead powered by modern steam engines. Yes, the ancient Egyptians also made some use of steam power, but as far as we know they never applied it industrially, and never via a reciprocating engine driving a rotary shaft. And yes, all of the qualifiers in the preceding sentence are necessary.

As we learn more about ancient civilizations, it will be interesting to see what other “modern inventions” turn out to have deep roots in ancient times!

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