1891 in technology

thumb|right|Reconstructed nyctograph, with scale demonstrated by a 5 euro cent. Nyctography (in Nyctography: ) is a form of substitution cipher writing created by Lewis Carroll (Charles Lutwidge Dodgson) in 1891. It is written with a nyctograph (a device invented by Carroll) and uses a system of dots and strokes all based on a dot placed in the upper left corner. Using the Nyctograph, one could quickly jot down ideas or notes without the aid of light. Carroll invented the Nyctograph and Nyctography as he was often awakened during the night with thoughts that needed to be written down at once,