Telegraphy the sense of a system that can transmit arbitrary messages over arbitrary distances. Lines of signalling relay stations can send messages to any required distance, but all these systems are limited to one extent or another in the range of messages that they can send. A system like flag semaphore, with an alphabetic code, can certainly send any given message, but the system is designed for short-range communication between two persons. An engine order telegraph, used to send instructions from the bridge of a ship to the engine room, fails to meet both criteria; it has a limited distance and
Law on the National Arms, Flag, and Anthem (Mexico) can be made or used. Article 4 states that the coat of arms will be made according to what was stated in Chapter 2 of this law and Article 5 states that certain officials, documents, seals and laws can be affixed with a special coat of arms. The difference with this coat of arms is that the entire arms is black and white, and the words "Estados Unidos Mexicanos" ("United Mexican States") appear in a semicircle at the top of the arms, between the olive branch and the oak wreath. Article 5 also states that the coat of arms can