In 1907 Ervin Samuel Mummer was operating a patternmaking and model shop, E. S. Mummert Co., in Hanover, PA, when he and Joseph S. Dixon developed a screw- and bolt-threading machine and an "oilstone" knife grinding machine. The Mummert company was reorganized as the Mummert, Wolf & Dixon Co. (the identity of "Wolf" remains unknown) which immediately began manufacturing the Dixon/Plurality screw machine and the knife grinding machine. They quickly added various bench grinders, tool grinders, and related products to their lineup, soon making five models of their popular oilstone grinders.

At the beginning of 1911 the company reorganized again as the Mummert-Dixon Co. The company continued with a similar product lineup for decades. In the 1950s, under the leadership of Charles McGough, Jr., the firm diversified through acquisitions, and then, in 1965, changed its name to CAM Industries, Inc. of Hanover. CAM Industries no longer makes the Mummert-Dixon grinders; they specialize in machines for making and repairing electric motors, machines for applying tape to wiring harnesses, and contract manufacturing. In 2005 the company reorganized as CAM Innovation.

Information Sources

• August 1905 Machinery, small text ad.

  Patterns and models are what we make: let us estimate on yours; work and prices will please you. E. S. Mummert Co., Hanover, Pa.

• 1907-06-07 The Iron Age, page 1713, has an illustrated article on Mummert, Wolf & Dixon Co.'s Quick Sharpening Edge Tool Grinder.
• 1907-07-11 The Iron Age.

  The Mummert, Wolf & Dixon Company, Hanover, Pa., which recently succeeded the E. S. Mummert Company of the same place, is placing on the market a new bolt cutter, which is known as the Plurality die bolt cutter. A number of sales of this tool have already been made and the demand is increasing. This company is also manufacturing a revolving oil stone grinding machine, particularly adapted for sharpening knives of woodworking machinery, for which a very satisfactory demand is reported.

• 1907-07-18 The Iron Age, page 164, has an illustrated article on the Plurality-Die Bolt Cutter.
• August 1907 Machinery, pages 706-707, has an illustrated article on the Plurality Die Bolt Cutter.
• 1907-09-26 The Iron Age.

  The Mummert, Wolf & Dixon Company, Hanover, Pa., reports some very satisfactory sales of its new Pluraility die bolt cutting machine, which is being placed on the market in three sizes. One machine has been furnished a customer in Hagerstown, Md., another to York, Pa., parties, while a third machine has been shipped to the Middle West. A good business is also reported in grinding machinery, and the outlook is considered very satisfactory.

• The 1908 volume of Southern Machinery has several articles on machines from Mummert, Wolf & Dixon Co.
• October 1909 Manual Training has an ad from Mummert, Wolf & Dixon Co. for their revolving oilstone grinder.
• The names and dates come from catalogs and ads submitted to this site; see below.
• Patent records provided the names of the principals. Besides the U.S. patents listed below, they also received a British patent, GB190812513.
• We discovered in March 2005 that the company's website was no longer accessible. In 2012, a correspondent notified us that the company was back online under a new name (and likely had been so for years).
• The OpenCorporates.com database entries for Mummert-Dixon provide some key dates.