In order to build a telegraph, a 12-volt battery, light bulb socket, wire cutters and more are needed. Get the right materials to build a telegraph with tips from a science teacher in this free video on building a telegraph.
Source: here
In order to build a telegraph, a 12-volt battery, light bulb socket, wire cutters and more are needed. Get the right materials to build a telegraph with tips from a science teacher in this free video on building a telegraph.
Source: here