(The following is adapted from Warren Devine): The impact of the shift from steam to electric power in manufacturing should not be forgotten. Between 1880 and 1930, for example, the production and distribution of mechanical power rapidly evolved from water and steam prime movers with shaft and belt drive systems to electric motors that drove individual machines. (More on the impact of the individual motor later.)
With electrification, the energy required to drive machinery was greatly reduced, and industry obtained greater output per unit of capital and labor input. "Reduced energy needs and increased productivity in manufacturing influenced the relationship between energy consumption and gross national product in the first three decades of the twentieth century".
I feel extremely fortunate in locating two photos that depict vividly an important component in woodworking history, and especially given that the differences in scale are so remarkable.
(The 1887 photo on the left shows a scene in the classroom for woodworking course at the St Louis (Missouri) Manual Training School (Established 1879). The photo on the right demonstrates how a home workshop can be set-up in 1930, with a Delta line of power tools, all driven by a fractional horsepower motor, thanks to the widespread availability of electric power for domestic use in the 1920s.)
Drive power is the issue. Today, we take for granted that a single electric motor drives each tool. Such an achievement betrays the long struggle woodworking -- along with other similar industries -- had to contend with (--- more later -- written 2-21-07)
In the late 1880's and early 1890's, far-reaching developments were under way, such as the use of electricity for street lighting and operating streetcars. This was the beginning of our present method of power distribution and has affected life in general,' and machine design in particular, more than any previous factor.
By 1906, direct-current motors running 720-900 or 1000 rpm were being used coupled direct to machine countershafts.; A machine thus driven individually could be located in the most desirable position in regard to work flow, as it no longer was necessary to place it in relation to lineshafting which was often inconvenient and clumsy.
Source: Judson H. Mansfield, "Woodworking Machinery: History of Development from 1852—1952", Mechanical Engineering: The Journal of the American Society of Mechanical Engineers, December 1952, pages 983-995. [some background info: Mansfield was Chief Engineer, Greenlees Brothers & Co., Rockford, IL, and the paper was ontributed by the Wood Industries Division and presented at the Fall Meeting, Chicago, Ill., September 8-11, 1952, of the ASME.
Sources: Calvin Milton Woodward, The manual training school, comprising a full statement of its aims, methods, and results, with figured drawings of shop exercises in woods and metals. Boston, D. C. Heath & co., 1887, page 26; Herbert E. Tautz and Clyde J. Fruits, The modern motor-driven woodworking shop; how to plan, operate and get the most out of it, Milwaukee, Wis., Woodworkers educational department (Division of Delta manufacturing co.), 1930, page 38; Judson H. Mansfield, "Woodworking Machinery: History of Development from 1852—1952", Mechanical Engineering: The Journal of the American Society of Mechanical Engineers, December 1952, pages 983-995; Warren D. Devine, Jr., "From Shafts to Wires: Historical Perspective on Electrification," Journal of Economic History 43 (1983): 347-372 [This is the article that started my quest for background on the impact of the lineshaft drive systems.];Jesse H. Ausubel and Cesare Marchetti, "Elektron: Electrical Systems in Retrospect and Prospect" Daedalus 125(3):139-169 (Summer 1996)