Index Arm

Some articles on index, index arm, arms:

Navigational Sextants - Adjustment
... Perpendicularity error This is when the index mirror is not perpendicular to the frame of the sextant ... To test for this, place the index arm at about 60° on the arc and hold the sextant horizontally with the arc away from you at arms length and look into the index mirror ... To test for this, first zero the index arm then observe a star through the sextant ...
Elton's Quadrant - Construction
... to a simple triangular frame and the addition of an index arm ... the backstaff is replaced with a sight (called an eye vane) mounted on the end of the index arm ... The index arm includes a nonius to allow reading the large scale with ten divisions between the graduations on the scale ...
Modern Technique - Celestial Navigation - The Marine Sextant
... The second component is the index arm, which is attached to the pivot at the top of the frame ... One mirror, referred to as the "index mirror" is fixed to the top of the index arm, over the pivot ... As the index arm is moved, this mirror rotates, and the graduated scale on the arc indicates the measured angle ("altitude") ...
Hindu Astronomy - Instruments Used
... Bhaskara II (1114–1185 CE) consisted of a rectangular board with a pin and an index arm ... backside was made as a quadrant with a plumb and an index arm ... altitude with the help of the plumb, time was calculated graphically with the help of the index arm." ...

Famous quotes containing the words arm and/or index:

    Four-room shack aspiring high
    With an arm of scrawny mast
    For the visions in the sky
    That go blindly pouring past.
    Robert Frost (1874–1963)

    Exile as a mode of genius no longer exists; in place of Joyce we have the fragments of work appearing in Index on Censorship.
    Nadine Gordimer (b. 1923)