Sailors use a real periscope to look above the surface of the water when they are in a submarine. You can make a device which will enable you to look over walls and around corners using mirrors. It only takes a few basic supplies most people probably have around their homes. This is an inexpensive school project if you can get adults to donate old makeup compacts or other small mirrors.
Things You'll Need
Two clean, empty quart milk cartons
Two square pocket-sized mirrors
Sharp pair of scissors or utility blade
Pencil or pen
Sturdy cardboard (optional)
Use the utility blade or the scissors to cut off the top of the milk carton -- the portion that looks like the roof top of a house. Cut it directly underneath where the milk pours out and discard the roof top-looking area. An adult may need to help you with this step.
Cut a square hole in the side of the milk carton with the blade or scissors. Draw a square with a pen or pencil to use as your guide. This needs to be as close to the bottom and front of the carton as possible. Make sure you leave a 1/4 inch space around the hole. This will help the mirror stay in place later. You can use the ruler to help you measure the frame around the hole that will help hold the mirror.
Place the carton down on its side on top of a table or other flat surface. Make sure the square hole you cut is facing your right side.
Use a ruler to measure 2 3/4 inches up from the bottom left side of the milk carton. Mark this spot with a pen or pencil.
Place the ruler so that it makes a slanted line from the mark down to the bottom right side of the milk carton.
Draw a line from the mark to the corner using the straight edge of the ruler as a guide. This will make an angled line.
Use the utility blade to cut out this line. Don't go all the way to the left side of the carton. You want your mirror to be able to slide into this slit, so use the blade to widen it if the mirror won't slip in without pushing too hard.
Slide the mirror into this slit. Make sure the reflecting side is facing toward the hole in the front of the carton. The reflecting side is the side you can see yourself in.
Tape the mirror in place with the masking tape.
Look through the hole. You should be able to see the ceiling or whatever is above you, such as the sky. If it looks tilted or odd, adjust the mirror and check it again.
Repeat the method on the second milk carton.
Position one of the milk cartons on the table so that the square hole you cut out is facing you.
Stand the other milk carton on the table, but place it upside down. The square hole you cut should be facing away from you on this one and the mirror on the top.
Squeeze together the open ends of the upside down milk carton just enough so that you can push it down into the other one about one inch..
Use the masking tape to tape the two cartons together.
Look through the bottom hole to see over obstacles, such as fences, that are taller than you. Look underneath tables by looking through the hole on top. Hold the periscope sideways to be able to see around corners.
Use half gallon milk cartons if you cannot find a mirror small enough.
Cut a square out of cardboard if the only mirrors you can find are round or oval, such as those in a makeup compact. Tape or glue the mirror to the cardboard with the reflective side facing out.
Heat an old CD or DVD with a hair dryer or hot water if you cannot find small mirrors. Use an utility blade or sharp scissors to cut the CD in square shapes. You ought to be able to get four square shapes out of each. (see ref 2 click on Instructions)