What is the origin of the sentence Now is the time for all good men to come to the aid of the party?

What is the origin of the sentence Now is the time for all good men to come to the aid of the party?

Never a political slogan, it was created as a typewriter exercise in 1867 by Charles E. Willer, a Milwaukee court reporter. The sentence was designed to use most of the keys on the typewriter, which had recently been invented by Willer’s friend Christopher Latham Sholes.