Uploads from bradmohr, tagged punchcard

200800953

nobody@flickr.com (bradmohr) — Fri, 11 Apr 2008 02:51:40 -0700

bradmohr posted a photo:

This is the device that was used to read the punchcards. A card would be placed on the metal platform and the handle lowered. Wherever there was a hole in the card, the corresponding pin would make contact and complete an electrical circuit, causing its associated dial to add one to its count.

200800955

nobody@flickr.com (bradmohr) — Fri, 11 Apr 2008 02:50:48 -0700

bradmohr posted a photo:

...then put the needle in the hole for each bit of census data.

200800956

nobody@flickr.com (bradmohr) — Fri, 11 Apr 2008 02:50:05 -0700

bradmohr posted a photo:

The operator would load a fresh card into the top section...

200800954

nobody@flickr.com (bradmohr) — Fri, 11 Apr 2008 02:52:47 -0700

bradmohr posted a photo:

50 of these machines were used to tabulate the 1890 census.

Pantograph Hole Punch

nobody@flickr.com (bradmohr) — Fri, 11 Apr 2008 02:49:24 -0700

bradmohr posted a photo:

This is a pantograph hole punch for punching the first punch cards ever (for the 1890 census). Herman Hollerith invented the punch card as a way to speed up the tabulation of the census. The 1880 census took 7 years to tabulate. Thanks to Hollerith, the 1890 census took just two and a half years (and the population total was complete in 3 months).