Note 19 — Chapter XXIII
Reading edition
It would be an easy matter to amuse the reader with an account of these improvements. One of the most notable of them consists in covering the back of the reflectors with white paint, for the purpose of increasing the light of the circular field. This scheme is identically the same as if the author had proposed to improve the magnificent telescopes of Herschel, when rendered dark with a high magnifying power, by white-washing the interior of the tube.