John H. W. Pettit letters to his family in England, illustrated with sketches by the writer, 1852-1868 - Page 187
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12
[words crossed out] may fancy if it cannot such time it is made use of be bought and set exactly to the same point, it will necessarily most materially affect the bush & [?] of the north -
The Theodolites in general use at home are superior to that which I have attempted to describe - but at the same time they are not at all suited for Bush surveying for this reason - the Needle is almost useless and cannot be wasted at all being so short and so much enclosed as to under [?] the to get a proper sight at or set at twice [word crossed out] within several minutes to the same point -
the only instrument which I have seen approaching to what I require was made by Adie of Edinburgh - the parts were few, its construction very simple, Excellent qualities for bush work [etc etc?] but in that even the needle was hardly good or long enough - Half the Compass Box was left quite open and clear - The upper half of the horizontal limb was made to work each pinion motion - The vertical limb was [?] and made to score as a standard for the Telescope which [?] round upon it by a rack motion for the purpose of raising and depressing it - One [?] was fixed upon the horizontal Limb - One on the Telescope [etc etc?]
The accompanying sketch Although doubtless in many respects incorrect will give some idea of the general construction