"key consisting of a lever that sends a telegraph signal when it is depressed and the circuit is closed"@en-us . "103477959"@en-us . . "0"^^ . "104230477"@en-us . . . . "04400737-n"^^ . . . "telegraph key"^^ . "telegraph key"@en-us . . "0"^^ . . . "104400737"^^ .