Improvements in or relating to indicating instruments

920,829. Actuation of switches. S. SMITH & SONS (ENGLAND) Ltd. Sept. 8, 1961 [Oct. 6, 1960], No. 34296/60. Class 38 (5). [Also in Group XIX] An indicating instrument, particularly for indicating the quantity of liquid in a fuel tank has a main pointer 2 on a spindle 1, which may be driven by the capacitative fuel gauging apparatus of Specification 695,074, and an auxiliary setting pointer 7 mounted for independent rotation about spindle 1. A pair of pins 9, 10 are rotatable around spindle 1 with the pointers 7, 2 respectively, pin 9 being carried by a gear-wheel 8 secured to a sleeve 6 carrying pointer 7, and pin 10 being carried by an arm 11 on spindle 1. Two cams 14, 15 are independently mounted on the spindle 1 and are urged together angularly by a spring 16. The gear-wheel 8 also carries a pair of microswitches 17, 18 which are operable by the cams and are settable with pointer 7 relative to pointer 2 by a knob 22, the gear 8 being held against rotation after setting by friction in the manual drive arrangement. When the two pointers are aligned, the pins 9, 10 are also aligned and the cams are separated by the thickness of the pins, the cams then being arranged to be in a position such as to open both switches 17, 18.