By the simplest of simple contrivances, I make this evil its own remedy.

An equable impulse given to the air produces an adequate uniform flow, preventing stagnation in one place, and excessive vehemence in another.

And the beauty of it is that by my new invention I make the air itself correct and regulate its own inequalities." "How clever you are, to be sure!" exclaimed Mary, wondering that her father could not see it.

"Oh, Willie, you will make your fortune by it! However do you do it ?" "The simplicity of it is such that even you can understand it.

All great discoveries are simple.