59. All knife-edges and bearings in weighing instruments shall be of hard steel or agate or of other material approved by the Board; they shall be so fitted as to allow the beam or steelyard indicator to move easily, and the knife-edges shall substantially near upon the whole length of their working parts.
60.—(1) All removable counterpoises weighing 1 ounce or more and all sliding poises on weighing instruments, shall contain an undercut adjusting hole or other means of adjustment.
(2) Any loose material used in any such counterpoise or poise shall be securely enclosed therein.
61. Weighing instruments with removable parts, the removal of which would affect their accuracy, shall be so construed that they cannot be used if any of the said parts are removed.
62. Where weighing instruments have interchangeable or reversible parts, the interchange or reversal thereof shall not affect the accuracy of the instrument.
63. All graduations on weighing instruments shall be so defined that the positions of all sliding poises or indicators are clearly readable.