Charles T. Porter

Trained as a lawyer, Charles Talbot Porter was admitted to the bar in 1847. A half-dozen years into his practice, a client gave as payment a half-share of the patent rights to a stone-dressing machine. The invention was based on sound principles but there were problems with the implementation. Porter found himself interested in the principles of mechanical design, and after a brief period of self-study was able to improve the stone-dressing machine's design to make it more practical. But then he ran into another problem: the steam engine powering the stone dresser rhythmically varied in speed, leading to a rippling of the stone surface. Careful investigation by Porter revealed that friction in the steam engine's governor was the root cause of its poor speed regulation. Porter's further study led him to an innovative design improvement where the spinning balls of the governor were made smaller so that they could be spun much faster. A counterpoise mechanism balanced out the force exerted by the spinning balls at the target rotational speed, and any variation in speed resulted in a much larger change in force than would be seen with the old-style governor. This simple idea, patented in 1858, proved to be very successful.

Porter licensed his governor design in overseas markets, e.g., to Ormerod, Grierson & Co., of Manchester, England. For the US market he established a shop on Thirteenth street, between Hudson and Ninth avenue, New York City, and began manufacturing his governors. He advertised his products in trade journals under his own name, Charles T. Porter. The original Porter governor design was not suitable for use in marine applications and so he developed a version specialized for that use that replaced the counterpoise weights with springs. His marine governor was patented in 1861 and also proved to be a great success. He had several years of good business. However, his governor was only suitable for use on single-stage steam engines, and as the more efficient compound steam engines gradually took over the market his governors would become obsolete.

Collaborations with John F. Allen and Charles B. Richards

In 1861 Porter met a young engineer, John F. Allen, who proposed a "variable cut-off" mechanism as a solution to defects he saw in Corliss steam engines. Allen's idea necessitated precise speed governing, and the two men realized that their two improvements complemented each other, and would result in an engine that could run much faster than existing steam engines, with corresponding improvements in smoothness and efficiency. They designed an engine incorporating their innovations, and had it built by McLaren & Anderson of Horatio street, New York. This engine was tested successfully and it immediately replaced the engine used to power Porter's shop.

Another improvement was necessary for the successful development of high-speed engines, namely a speed indicator that could measure several hundred RPMs. Charles B. Richards developed such an indicator, which was licensed by Porter.

After the success of the first Porter-Allen engine, a second engine was built to be exhibited at an International Exhibition to be held in London in 1862. Porter's plans to exhibit the engine were nearly thwarted by exhibition officials who were dubious that an engine could be safely run at those speeds, but he ultimately prevailed. His exhibit included the Richards indicator, and that led to it being licensed for manufacture by Elliot Brothers of London.

Porter ended up spending nearly six years in Europe: exhibiting his engines, having new and improved engines built for him, and talking to other engine builders. One of his improvements was to add a condenser of his own new design to his engine, as the UK market insisted on condensing engines. During his time in Europe Porter did considerable work on the techniques and tools for manufacturing engines, many of these improvements aimed at producing more refined parts that were suitable for use at high speeds.

Porter's efforts on high-speed engines generated considerable interest both in Europe and in the US. He returned to the United States in 1868.

Building the Porter-Allen Engine

Porter partnered with John F. Allen and set out to manufacture the Porter-Allen engine from a small shop in Harlem, as the Porter-Allen Engine Co. Expansion required them to raise more money. Progress was slow. The Financial Panic of 1873 proved to be a major setback for the struggling business, which abandoned the manufacture of engines but continued to work on improvements. The Financial Panic led into the Long Depression. In about 1876 Porter and Allen contracted the manufacture of the now-improved Porter-Allen engine to the Hewes & Phillips Iron Works of Newark, a builder of machine tools whose shop floor had been idled by the Depression.

In 1880 a Porter-Allen engine was installed in the Edison laboratory at Menlo Park, in order to drive an electric generator. This led to considerable follow-on business from Edison and others for "steam dynamos", a generator directly coupled to a high-speed steam engine. Another important market for the Porter-Allen engine was in steel mills, where the high-speed engine led to productivity improvements in rolling steel.

We have seen an engine labeled as "The Porter-Allen Engine / Made By / Charles T. Porter / Newark, N. J." It is uncertain whether Porter really did manufacture this engine or whether it was made by Hewes & Phillips. In any event it would seem that Mr. Allen was no longer involved in the business.

Eventually the manufacturing of the Porter-Allen engine would move to the Southwark Foundry & Machine Co. of Philadelphia. Throughout over 40 years of manufacture, the Porter-Allen engine remained virtually unchanged, and this is true not only of the engines built on behalf of the Porter-Allen Engine Co., but also those under the Sounthwark Foundry name, and also those built in the UK by Tangyes Ltd.; Tangyes (and others) built unlicensed near-exact copies of the Porter-Allen design once the patents had expired.

The fate of the Porter-Allen Engine Co. is murky. The company seems to have faded from existence by the late 1870s. At some point, probably in the late 1880s or early '90s, set up an engineering consulting business in New York. He also wrote for the trade journals. articles that were noted for their clear and elegant prose. He died in August 1910.

Information Sources

• Ads 1860 issues of American Railroad Journal for Porter's Improved Centrifugal Governor,from Charles T.Porter of 235 West 13th St., New York.
• 1875 report, The Porter-Allen Engine: Report on Its Practical Performance, Economy, Durability, Etc., by A. L. Holley.
• 1881 report on The Albany and Rensselaer Iron and Steel Works, Troy, New York. Page 5 shows an image of an engine with label, "The Porter-Allen Engine / Made by / Charles T. Porter / Newark, N. J."
• 1885 book, Steam Using; or Steam Engine Practice, by Charles A. Smith. On page 111, in discussing expansion curves for the Porter-Allen Engine. "They are given as an example of the most skillful design which has been attempted with the best workmanship ever used in engine building." Pages 167-187 provide detailed drawings of every aspect of the Porter-Allen engine.
• 1895 Description of the Porter-Allen Steam Engine, Southwark Foundry and Machine Co. This catalog strongly suggests that the Porter-Allen Engine Co. no longer existed, and the Porter-Allen engines were being sold under the name of the Southwark Foundry & Machine Co., "Sole Makers."
• March 1903 The Steamship pages 327, article by John E. Sweet, "Recollections of the Early Days of the High-speed Engine Industry".
• December 1903 The National Engineer, page 80. "The first Porter-Allen automatic engine, as a commercial proposition, was brought out in 1874." This contradicts our history that suggests that Porter-Allen engines were made in a small way beginning perhaps in 1868 or '69, were waylaid by the Financial Panic of 1873, and then resumed in 1876 when Hewes & Phillips took over manufacture.
• 1908 Engineering Reminiscences Contributed to "Power" and "American Machinist", by Charles Talbot Porter, 335 pp.
• American Steam Engine Builders: 1800-1900 by Kenneth L. Cope, 2006 page 194