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Show I f148] 50 ., ,By help of these, the .moon's Al and hourly motion at transit "- were computed from the moon-culminating list of the Nautieal · Almanac, using fourth differences. A comparison of the computed A=t with that observed, gave the nu~erat.or-the hourly motion being the denominator-of the fraction expressing the correction of the : ·,1assumed longitudes. Those corrections, and the resulting longi· tudes, are as follows: m. s. h. m. s. \ l. +O 15.52 6 58 4.5.52 '' II. -1 15.65 7 · 28 15.35 III. -0 37.54 8 07 42.46 IV. +4 36.70 .8 06 28.70 ·' Camps-I and II, as well as III and IV, being connected by chro- ' non.etric differences, it becomes important to test the results above given by a comparison of the two differences. We have then / By .Junars . ...•...•...........•...• .By chro . .....................•..•. L-C ............... _. ....... , .... . m. s. 29 29.83 29 33.83 -4.00 m. s. 1 13.76 1 10.67 +3.09 The chronometric difference is adopted as the most exact-ap· portioning the errors of the other among the longitudes by lunars, i 'remembering that camp II is determined by a single culmination, ,whi'le at each of the others two were observed, we , should now have, were the lunar tables correct, the best system of longitudes. Mr. S. C. Walker states that· a correction of the present residual errors of the lunar table11, would increase all the longitudes depenq· i~g upon moon culminations by about six seconds of time. Adding, therefore, six seconds to the above corr¢cted longitudes, we get finally, as the basis of the whole work, the followin'g adopted longi-tudes. 1 I · I h. m. s. 0 ' ,, August 22, 1844 . . . . . . . . . . . • 6 i58 50.72=104 42 41 I. .M:huth of the ontaine-q~· -bouit, \ II. Camp at Sa t Ltake, ctober : ( 14, 20 : ... . ......... : . . . . . '7 28 ' 24.55=112 06 08 0 1II.· Lassen's farm~ Deer creek Ap l'il ' 14, 184'6 ........ ' .......... '8 107 46.92=121 56 44 : IV. - Buttes Sacr1a en to valle~, June : : 4, 1846 . ·..• .. • . .. . • .. • • . .. • s lo6 36.24=121 39 o.t ~ pon. these an~ the sextant observations, is based the accompanytng table of lahtut~es and longituJes. J. S. HUBBARD. ' OBSERVATIONS WITH THE TRANSIT INSTRUMENT. . ' ... • / |
