John H. W. Pettit letters to his family in England, illustrated with sketches by the writer, 1852-1868 - Page 185

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steady true to its work, turning just clear of the divided edge of the box - one that can always be set exactly to the same point - reading of course any difference of bearing upon the Horizontal limit -
Mind I don't want a circumferentor but a Theodolite, embracing and combining the advantages of a good circumferentor -
I also [?] a powerful microscope to read the needle - but the difficulty of always placing the eye in exactly the same position exists - of course [word crossed out] moving a little on either side makes a difference - perhaps a sight might be fixed immediately above.
The Cardinal point which is left open [words crossed out] to act as a guide -
Dark glass for observing the sun -
Plumb bob -
Microscope -
screw driver -
sun shade -


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