----- B-52 navs used to say, "We measure it with calipers, mark it with a grease pencil and chop it with an ax."
"Calipers" refers to trying to get very fine/precise readings in bearing and elevation of the celestial body on the sextant. "Mark with grease pencil" refers to the occasional dull pencil which could plot a line on some charts nearly a mile wide. "Chop it with an ax" refers to navigator judgment which sometimes leads him/her to put more weight/value on one celestial observation than another or to place more value on DR position (dead reckoning position obtained by plotting heading, air speed, time and wind/drift) than on the celestial info. Wilton
