The Pros And Cons Of The Sextant

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“History is the sextant of states which, tossed by wind and current, would be lost in confusion if they could not fix their position” said Allan Nevins, an American historian and journalist. The sextant was invented in 1757 by John Campbell in Scotland. John Campbell innovated the octant, created by John Hadley, by increasing measuring angles. Sextant came from the Latin word “sextus” which means one sixth. Though the sextant was helpful for navigation, the design itself had many errors. The pros about the sextant are navigable, modern use, and relic. The main purpose of the sextant is navigation. The “instrument [is used] for determining the angle between the horizon and a celestial body… or… to determine latitude and longitude” (Sextant). …show more content…

Though the invention was useful for navigation, the design has many flaws that are non-correctable. “Graduation error… are caused by imperfections in machining the arc, cutting the gears, or marking the scale of the arc or micrometer drum” ((The Marine Sextant (Correctable and Non-Correctable Errors)). Another non-correctable error is the prismatic, which “is caused by the planes of a mirror not being parallel” ((The Marine Sextant (Correctable and Non-Correctable Errors)). The last non-correctable error is centering which occurs “when the index arm is not pivoted at the exact center of curvature of the arc” ((The Marine Sextant (Correctable and Non-Correctable Errors)). Another set of errors the sextant has is correctable ones. One of the correctable errors is the index error caused when “the horizon glass not being parallel to the index mirror when the sextant is set on zero” ((The Marine Sextant (Correctable and Non-Correctable Errors)). Error of perpendicularity is the “results from the index mirror not being perpendicular to the sextant frame” ((The Marine Sextant (Correctable and Non-Correctable Errors)). Similar to the error of perpendicularity, side error is caused when “the horizon glass not being perpendicular to the frame of the sextant” ((The Marine Sextant (Correctable and Non-Correctable Errors)). The design of the sextant is inconvenient due its size which took a proportion of space on boats. There are

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