“The Industrial Instrument—Master of Industry, Servant of Management”: Automatic Control in the Process Industries, 1900–1940

Abstract

Research Notes “THE INDUSTRIAL INSTRUMENT—MASTER OF INDUSTRY, SERVANT OF MANAGEMENT”: AUTOMATIC CONTROL IN THE PROCESS INDUSTRIES, 1900-1940 STUART BENNETT Herbert H. Dow, founder of the Dow Chemical Company, opined in 1930 that industrial development rested on three basic technical ad­ vances: “firstly the steam engine inaugurating power production,” then interchangeable parts “making possible mass production,” and third, an “advance still in its infancy, automatic operation by automatic con­ trol ofcontinuous processes.” He thought the latter occupied a position in the process industries akin to that of interchangeable parts in the assembly industries.1 From the 1890s onward, Dow sought to reduce the number of people employed in the production process. His strat­ egy was to increase plant size, use automatic analysis and automatic operation of the equipment governed by automatic analysis, and de­ velop automatically controlled and operated continuous processes. By automatic control Dow meant closed-loop feedback control, and the Dow Chemical Company developed its own electrically operated controllers during the 1920s.2 During this same period, specialist Dr. Bennett, a lecturer in the Department of Control Engineering, University of Sheffield, completed the work for this article during his tenure as a senior postdoctoral fellow at the National Museum of American History (NMAH), the Smithsonian Institution. He is grateful for financial support from the Smithsonian Institution fellowships and grants program and from the University of Sheffield, and to the NMAH Division of Engineering and Industry for providing a base from which to work. He thanks Carlene Stephens and Barney Finn, his fellowship advisers, for their support and encouragement; Carlene Stephens, Jeffrey Stine, Steven Lubar, Maureen Whitebrook , and Peter Liebhold for reading the manuscript and suggesting improvements; and Jim Roan of the museum library and the division staff for research assistance. ‘Herbert H. Dow, “Economic Trend in the Chemical Industry,” Industrial and Engineering Chemistry 22 (1930): 113-16. Dow’s views were summarized in the January 1933 issue of the Industrial Bulletin of Arthur D. Little, Inc., and an extract from this summary was quoted in an editorial entitled “Industry’s Third Horizon?” Instruments 6 (February 1933): A5. ’The Dow Chemical Company first attempted to introduce automatic control in 1894; see Dow, p. 115. It continued to develop its own controllers until the early 1930s;© 1991 by the Society for the History of Technology. All rights reserved. 0040-165X/91/3201-0005$01.00 69 70 Stuart Bennett instrument companies extended their product range from indicators and recorders to include electrically and pneumatically operated feedback controllers. These instruments were the forerunners of the pneumatic and electronic controllers that were to play a major role in automating a whole range of industries during the 1950s.3 The process industries to which Dow’s techniques for reducing labor could be applied include metals, power generation, petroleum, chemicals, food, textiles, paper and pulp, glass, ceramics, brewery and distillery, sugar, lumber, and paint and varnish. The Works Progress Administration (WPA) surveyed these industries for the period 1909—35 for a project that culminated in a report, Reemployment Opportunities and Recent Changes in Industrial Techniques. Published in 1938, this WPA report found that there was a very rapid growth, in both absolute terms and relative to other forms of machinery, in the sales of industrial instruments between 1919 and 1929.4 And although the absolute value of sales of instruments fell sharply during the Depression, instrument sales relative to sales for all machinery continued to increase, moving from approximately 0.4 percent of machinery sales in 1919 to 1.4 percent in 1935, with a peak of almost 1.6 percent in 1933. The instruments included in the survey were indicators, recorders, and automatic feedback controllers, and, by 1935, the sales were roughly one-third indicators, one-third record­ ers, and one-third controllers. There was a rapid increase in the see John J. Grebe, Ray H. Boundy, and Robert W. Cermak, “The Control of Chemical Processes,” Transactions of the American Institution of Chemical Engineers 29 (1933): 211-55. This was one of the first technical papers on industrial process control. ’To introduce automatic feedback control, three components are needed: a measur­ ing instrument to convert some physical quantity to an electrical or...