The telegraph machine, invented by Samuel Morse, transmits signals through wires to send messages. Follow this guide to build a telegraph machine and send messages without saying a word.
- TIP: Use pliers to bend the tack over on the other side of the cardboard so the wire is firmly attached to the tack and won't fall out.
- Step 1: Tie a loop in the free end of the second long wire and in one end of the remaining short wire, and hook both wires around the tack that is directly under the switch on the second piece of cardboard.
- Step 2: Tape the light to the second piece of cardboard. Tape the free end of the short wire to one of the light's wires and tape the free end of the first long wire to the other light's wire.
- Step 3: Tie a loop in the free end of the third long wire. Hook the loop around the tack that is on the underside of the switch of the second piece of cardboard. Now the electric circuit is complete.
- FACT: On May 24, 1844, Samuel Morse stretched wires from Washington, D.C., to Baltimore, Maryland, and sent the message, "What hath God wrought?"
- Step 4: Press down on the switches. Depending on what switch you press, the flow of electricity through the wires will turn on the light or sound the buzzer allowing you to send light or buzzer signals from one piece of cardboard to the other.
- TIP: Tape the long wire to the red wire so the wires stay connected.
- Step 5: Twist one end of the third long wire to the red wire that is attached to the buzzer.
- Step 6: Tape the battery in the center of one of the large pieces of cardboard. Tape the buzzer to the other side of the battery. A black wire and a red wire stick out from the side of the buzzer.
- Step 7: Press two tacks through both larger pieces of cardboard directly under the switches. Then press two tacks through the underside of both switches. When you push the switches down, the tacks must touch.
- Step 8: The metal parts of both wires must touch, so strip the ends. Tape 2 of the shorter pieces of wire to the negative side of the battery and loop one of the wires around the tack that is under the cardboard switch. Connect the second short wire that is taped to the battery to the black wire that is connected to the buzzer.
- Step 9: Loop one of your long wires around the tack that is on the underside of the switch. Tape a second long wire to the positive end of the battery.
- TIP: Use tape to label your long wires with letters or numbers to avoid confusion.
- Step 10: Tape each small piece of cardboard to the end of each large piece of cardboard. Bend the small pieces of cardboard upwards at the tape. Your small pieces of cardboard will be your switches. Place the large pieces of cardboard next to each other.