“Yes, Tom; and the more light they gather.”
“Well, then, why do you say, uncle, that you don’t look through the glass?”
“Because it is a fact that I want you to understand,” said Uncle Richard, smiling. “The big glass, or in our case the reflecting speculum, forms a tiny image of the object at which it is pointed, close to where we look in, within an inch or so of our eye.”
“A tiny image, uncle?”
“Well, picture, then.”
“But you say tiny! It looks big enough when we put our eye to the little round hole.”
“To be sure it does. But what do you look through?”
“The eye-piece.”
“Well, what is the eye-piece?”
“A little glass or two—lenses.”