collars to the micrometer held. Fig. 2.123. Inside Micrometery (Commercially available inside micrometer set). This form of internal micrometer is, in effect, merely an adjustable end measuring bar. As in the case of an ordinary external micrometer, there is a barrel and a thimble, but no frame and no spindle.
Fig. 2.89. Type B Vernier Caliper. Fig. 2.90. Beam and Vernier for Vernier Calipers having least count of 0.05 mm. Graduations on beam at every 1 mm and each 5 mm line extended and each 1 cm line is numbered. On vernier scale there are 20 divisions within a distance of 19 mm and 19 mm = 19 divisions of main scale.