All of these substances can be purchased today anyway, and the recipes are readily available in the library. The recipes are presented to show how chemical technology was built up from the simplest starting materials. There are some preparations here that would be really fun to try, and not too difficult. These do not involve substances more dangerous than those found under the kitchen sink and elsewhere around the house, and do not require methods that are more difficult and dangerous than baking a cake. Still, let your good sense be your guide.
Danger is our Number One Safety Problem.
If you don't know what you're doing, don't do it.