Today in Tech History – October 21, 2017

Today in Tech History logo1879 – Thomas Edison finished up 14 months of testing with an incandescent electric light bulb that lasted 13½ hours. It improved on 50-year-old technology to make light bulbs safe and economical by using lower electricity, a carbon filament and an improved vacuum.

http://learning.blogs.nytimes.com/2011/10/21/oct-21-1879-thomas-edison-lights-the-lamp/

1949 – An Wang filed a patent for a magnetic ferrite core memory, that he called pulse transfer controlling devices. Two years later he formed Wang computers.
http://www.google.com/patents?id=JSNjAAAAEBAJ&printsec=abstract&zoom=4#v=onepage&q&f=false

1983 – The seventeenth General Conference on Weights and Measures ruled the meter would be defined as the distance light travels in a vacuum in 1/299,792,458 of a second. This actually simplified it from the previous definition of 1,650,763.73 wavelengths of the orange-red emission line in the electromagnetic spectrum of the krypton-86 atom in a vacuum.

http://arxiv.org/pdf/0810.3512.pdf

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