What hides this stereogram?
Brain Teasers
[3801] What hides this stereogram? - Stereogram - 3D Image - #brainteasers #stereogram #3Dimage
2017-04-14
Edison patentIn 1873, Thomas A. Edison was issued a U.S. patent for an "Improvement to Circuits for Chemical Telegraphs" (No. 135,531). It concerned a method to reduce the problem of marks running together on the chemical paper from the electric action of one pulsation from the telegraph wire not clearing before the next followed. Edison utilized electromagnets in local or branch circuits to sharpen the pulses. |
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