About the Images

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This photograph shows a Hollerith punched card as used by the US Census being punched pantographically by an operator. The photograph is circa 1940; it isn't clear if this is equipment as used for the 1940 Census or if it is a posed picture illustrating the use of earlier equipment. This image is from the US Bureau of the Census, US Department of Commerce. It is now in the U.S. National Archives and Records Administration and is available via Wikimedia Commons at: http://commons.wikimedia.org/wiki/File:This_is_a_card_puncher,_an_integral_part_of_the_tabulation_system_used_by_the_United_States_Census_Bureau_to_compile..._-_NARA_-_513295.tif NARA ID: NARA-513295. It is in the public domain worldwide as an official US federal government photograph.

In addition to representing "data" thematically, and showing a machine developed in the 1880s (for the 1890 Census), this image has a further resonance with ATF and the Barth. The pantographic punching machine shown is of the single-arm type (known since at least the 18th century - James Watt used one in his retirement for duplicating 3-D objects). Two of the five pantographs developed by Linn Boyd Benton were also of the single-arm type. Both of these are the styles of his pantographs that we most commonly think of today. The first of them, from 1883/4 (patented 1885) represented the second use of pantographs in type-making (soon after the first use, of a horizontal-format pantograph by the Central Type Foundry in 1882). ATF did much to publicize its use of these vertical-format Benton machines.

But there is an issue with allsingle-arm pantographs: necessarily, they distort either the pattern or the workpiece. This must be compensated for, either by distorting the pattern to produce a desired workpiece or by accepting the distortion in the workpiece. Here's a better view of the single-arm pantographic Hollerith punch. The distortion necessary in the template is apparent.

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(Photographed on 2012-01-28 by Wikimedia Commons user Arnold Reinhold at the Computer History Museum. Online at: http://commons.wikimedia.org/wiki/File:Hollerith_card_punch.agr.JPG Licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported license.)

To the best of my knowledge (as of 2016) we do not know which solution Benton adopted (deliberately distort the pattern, or accept the distortion in the workpiece), or, indeed, if he was even aware of the issue.