Object: Some test tubes.

Good morning, boys and girls. How many of you have ever been in a laboratory or seen a laboratory in the movies? In the movies there are always a lot of men walking around in white coats watching some steam or smoke coming out of some test tubes. I am sure that you have seen something like this, haven't you? [Show them the test tubes.] I think test tubes are really neat little things. They make everything that fills them up look scientific. I once knew a little boy who drank his milk out of test tubes. But test tubes were not made to drink milk out of, or anything else like that. Test tubes were made to test things and make sure that they are all right before they are used. And you don't usually just test things in them once. You test a secret formula hundreds of …