Draw A Perfect Spiral

Do you need to draw a spiral? Here is a foolproof method how.

Steps

Get the things you'll need.
Put the paper on top of the phone book.
Cut a piece of string that is {{safesubst:#invoke:convert|convert}} longer than the distance from the center of the paper to where you want the outer edge of the spiral to be.
Put the end of the string onto the centre of the paper and stick the thumbtack into it so that it stays. Push down on the thumbtack very hard.
Tie or tape the other end of the string to the tip of the pen or pencil.
Pull the string taut, then put the tip of the drawing implement to the paper.
Pull the pen or pencil to the left or the right. It doesn't matter which, as long as you keep going in the same direction.
If you have followed the preceding steps accordingly, the line on the paper should spiral inward.
When you have reached the thumbtack, stop pulling the pencil or pen and remove the thumbtack.
Congratulations! You have just drawn a spiral!

Make sure that the tape doesn't obscure the marking part of the pen or pencil.
It is sometimes useful to mark the center of the paper with a pen or pencil first, just in case.
The phone book is so that you don't ruin your table.