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Show 97 [ 243] REMARKS. ,..rhe maps whid1 accompany this report me on Flamsteed,s m~dified projection, and the lono-itudes arc referred to the meridian of Grecnw1ch. · F'or the deterrnin~t.ion of astronomical positions ,,.e were provided wil!t the following instruments : One tcltscope, magnifying power 120. One circle, by Gamb~y, Paris. One sextant, by Garnbey, Paris. One sextant, by '1\oughton. One box chronometer, No. 7, 10, by French. 011e Brockbank pocket ch ronomcter. One slllall watch with a light chronometer balance, 1\o. 4,G32, by Arnold "~ Dent. The rate of the chronometer 7, :")10, is exhibitell in the follo\vinrr s! at ~. ment: "NEw Y onK, ~1fay 5, lS·L~. tc Chronometer 1\o. 7,810, by French, is this day at noon, " Slow of Greenwich mean time - 11' t1 '' " I(,a~t of New '{ ork mean tin1c 4ft 45' 1" " Loses per (by 2'' 1 7 0 "AR1.,1IUR STE \iVART, " 7 4 JlJercltants' J•).7:chau rre., An accident, amonrr some rough ground in the neighborhood of t I H~ J{nnzas river, strained the balance of this chronometer (No. 7, I 0), a11ti rendereJ it useless during the re;nainder of the campaign. From the 9tl1 of June to the 24th 0f August incl usively, the longitudes depend upon th t' Brockbank pocket chronometer; the rate of which, on leaving Sr. Lo u i ~, was fourteen seconds. 11 he rate obtainetl by observations at Fort J ~•uan t ie, 11''.05, has been used in calculation. From the 24th of Aug11st until the termination of the journey, No. 4 ,Ga~, of which the mte was 35''.79, was used for the same purposes. 'rhe rate gf this watch was irregular, anu I place but li ttle confidence in the few l o n~Jt. udes which depend upon it, thotwh, so far as we have any mean::; of jnJ~ ing, they appem tolerably correct. o |