A film by the American Telephone and Telegraph company, showing through both animation and live action how to use the rotary dial of the telephone. A woman shows how the numbers should be dialed and the mistakes that should be avoided, such as dialing before having picked up the receiver or not finishing the series of numbers properly.
The first telephones of the 1870s were arranged in pairs, meaning that one could only call up the person with the other telephone. With the invention of the telephone exchange, callers could be connected to other numbers and switched between lines. The first commercial telephone exchange in the United States opened in Connecticut in 1878. The video above shows the change to automatic switching, meaning that one could dial the number without having to go through the telephone exchange, although dialling number 8 does connect the caller to the information centre where a group of women are frenetically looking through telephone directories in order to find the telephone number needed.