“This I did shortly afterwards, my basis being the theory of refraction. First I prepared a tube of lead , at the ends of which I fitted two glass lenses, both plane on one side while on the other side one was spherically convex. Then placing my eye near the concave lens I perceived objects satisfactorily large and near, for they appeared three times closer and nine times larger than when seen with the naked eye alone .”

− Galileo Galilei published the initial results of his telescopic observations of the heavens in Starry Messenger (Sidereus Nuncius) in 1610