If then we can only make this light _available_, it is clear that we shall have acquired a large increase of _light_ from the distant object.

Now it will be noticed that the light which has converged to _p_, diverges from _p_ so that an eye, placed that this diverging pencil of rays may fall upon it, would be too small to receive the whole of the pencil.

Or, if it did receive the whole of this pencil, it clearly could not receive the whole of the pencils proceeding from other parts of the image _emf_.
_Something_ would be gained, though, even in this case, since it is clear that an eye thus placed at a distance of ten inches from _emf_ (which is about the average distance of distinct vision) would not only receive much more light from the image _emf_, than it would from the object EMF, but see the image much larger than the object.

It is in this way that a simple object-glass forms a telescope, a circumstance we shall presently have to notice more at length.

But we want to gain the full benefit of the light which has been gathered up for us by our object-glass.