The story
From telegraph + -y (suffix forming abstract nouns), q.v., equivalent to tele- (“far, distant, telegraph”) + -graphy (“writings on a subject, area of study, etc.”).
Etymology from Wiktionary, CC BY-SA 4.0.
telegraphy
Today it means: Any process for transmitting arbitrarily long messages over a long distance using a code, especially by means of electrified wires or radio waves using Morse code. Full definition →