§ 62. Polishing. — [*]
§ 63. Centering. — [*]
§ 65. Preparing Small Mirrors for Galvanometers. — [*]
§ 66. Preparation of Large Mirrors or Lenses for Telescopes. — [*]
§ 69. The Preparation of Flat Surfaces of Rock Salt. — [*]
§ 70. Casting Specula for Mirrors. — [*]
§ 71. Grinding and polishing Specula. — [*]
§ 72. Preparation of Flat Surfaces. — [*]
§ 73. Polishing Flat Surfaces on Glass or on Speculum Metal. — [*]
CHAPTER III [*]