Refracting telescopes - use a large lens to gather and focus the light.
(Refracting telescopes; use; a large lens; to gather and focus the light) Context(Refracting telescopes use,List([0, 27))):(Refracting telescopes; use a large lens to focus; the light)
Refracting telescopes use,List([0, 27))
Refracting telescopes Refracting telescopes
use use a large lens to focus
a large lens to gather and focus the light
the light