Coherent Identifier About this item: 20.500.12592/c90swn

Journal of the Asiatic Society of Bengal Part I June 1843

1843

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Summary

The altitude of the sun or moon ' when on the meridian can be read off with equal ease and the latitude of any place ascertained with the aid of a Table of Declnation pasted on the lid of the box. [...] For instance the most approved method of laying down a mridian is said to be by observations of equal altitudes of the Polestar ; but without the Nautical Almanac for the year which is not always to be obtained it often requires nights of watching and the patience of a Chaldean to catch the star in the small field of a Theodolite telecope at the precise moment necessary for the accuracy [...] To find the meridian line place the instrument or rather the line E C due north and south by any compass C being the north point and E the south at any time (arty an hour) before noon ° the sun will be observed to shine through the hole L throwing a bright round spot on the left side of the plate near one of the circles a t a a; wait till the spot comes on the circle say at G and mark the [...] Divide by 2 which gives 400 or the bisection of the arch G H move the radius to the point of the rim marked 10° which is half way (or 40°$) between the extreme $oints G and H. The direction of the radius as now placed will be that of the true meridian being the bsection of the arch G H described by the sun himself (the great Archimedes) at equal altitudes.§ The instrument having been ori [...] The obverse of these coins accordingly represented the bust or the head of the king together with his title and name while the rverse contained a cross and the name of the mint-master or the town or of both in the Latin language.

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Pages
109
SARF Document ID
sarf.120250

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