146 



ASTRONOMY. 



one efjiiatiorij aluajH sniall, and vanishing at no great distance from the equator, being intro- 

 iliiced when necessary, and the requisite correction for the chronometer rate hcing applied, it is 

 evident that but two equations arc necessary for the determination of the unknown quantities. 

 One is generally furnished by a circum-polar star ; the other by the mean of the equations, 

 corresponding to all the stars near the moon's pathj in order the more completely to remove all 

 chance of constant error from the desired result. The equations being solved, furnish the 

 quantities given below, and which have been applied to the observations. 



The first column contains the date ; the second the name of the object observed ; the third 

 shows the position of the instrument, (lamp east or west.) Next follow columns 4, 5, 6, 7, 8, 

 9, 10, the seconds of observed transit, and column 11, the mean of the transit over as many 

 wires as have been observed. Colunm 12 contains the correction to be applied to this mean 



for an 



(n + c) 



feet 



+ 



(sec. d 



the correction for instrumental error, or the quantity 

 tan. d,) the last term of which is generally equal to o; and 



column 14 gives the correction of chronometer, and the constant term of instrumental correc- 

 tion, or the quantity A / -j- m. 



In cases where a mean- time chronometer has been used, this column includes also the 

 reduction of mean to sidereal time, the quantities in all the preceding columns being in mean 

 time. In column 15 is given the sum of the quantities ; in columns 11, 12, 13, and 14 are the 

 obBcrved right ascension of the object ; and the last column shows the tabular right ascension^ 

 taken in the order of preference from the Nautical Almanac, the Greenwich Twelve-year 

 Catalogue, or the Catalogue of the British Association. 



The next step was to deduce the required corrections of the assumed longitude of the jdace, 

 by comparing the observed AR. of the moon with that corresponding to the assumed longitude 

 already determined very approximately by computations in the field. For this purpose, the 

 tabular AR. was interpolated from the moon culminating list of the Nautical Almanac, using 

 fourth diiferences, and it was found that the assumed longitude corresponded i^erfectly to the 

 results, from the uncorrected tabular place of the moon. But the extracts from the observations 

 at Greenwich, given below, show a correction of the latter to be necessary ; and this bein 

 applied, the corresponding correction of the assumed longitude was determined and also applied. 





Constant values emiyloycd in the reductions. 



O] 



t ■* ' 



.VATORT AT CAMP RlLKY, 



I^.^(orial minvirh of transit wires. 



I. 



n. 



III. 



IV. 



+ 51.163 +33.971 +n!l65 +0.22 



V. 



17.092 



VL 



34.089 



VII. 



OBSERVATORY X£AK JLACTIOS OF THE GILA A>D COLOJIADO RIVBBS, 



Equatorial intervah of iransU wirft* 



T. 



IL 



III. 



IV. 



51 



.141. 



July 27..., 



28,... 



^J ■ • » » 



31.... 



Ang. 2..., 



3..,. 



26.... 



27.... 



Sepl. 3,... 



^ « « • « 



O.flOO 

 0.000 



0.000 



O.OOQ 



- 0.770 

 -0.726 



- QS^ 



- 1.85-i 



- 2.fi94 



— 2.-2:n 



- 1.778 



- 2.613 



- 2.4*>7 



At-\- 



m 



+ 11.99 

 + 12.50 

 12.48 

 12.45 



12.20 



12.(53 

 iO.&^> 

 6.32 

 6.30 

 6.2:? 

 5.87 

 1.B4 

 + 0.49 



n-\- c At-\-m, 



•Sept, 5... 



34... 

 27... 



28... 



• "J ... 



Oct. 93... 

 25... 

 28... 



29... 



Nov. 1 . . . 



9 .. 



3* • • 



+ 2.716 



+ 1.388 



+ 1 041 

 + 0.792 

 + 1.I2J 



+ 1.204 



+ 0.<*34 

 + 1.471 



+ 1.12*^ 



+ 1.764 



+ 1.764 



+ 1.764 



0.000 



A. m. 



-2 25 



2 24 



■2 24 



2 24 



■2 24 



2 24 



2 23 



2 23 



9 23 



2 23 



2 -23 



2 23 



2 23 



5. 



29.02 

 54.55 

 47.68 

 45.66 



43.^3 



42.23 

 54.74 

 48.95 

 40.42 



38,&5 

 31.26 

 28.09 

 ^ . .14 



»' »- *. ». 



+ 52.790 +35.078 +17.467 +0.44 



V. 



17.489 



VI 



35. ISO 



vu. 



52 ,'710 



« + C. A < + 7/1. 



Oct. 3..., 



' ft • • « 

 d« . « • 

 6», . . 



7 



' » • * « 



24..., 



-mIJ* a ■ • 



^^ V ft • ■ 



27.... 

 28.... 

 99.... 



^Tv .... 



'H .... 



1.026 

 0.450 

 0.000 

 0.878 

 29.100 

 1.410 

 0.450 

 0.437 

 0.147 



0.297 

 0.607 

 1.435 



1.238 



+ 

 + 



4- 

 + 



+ 



12 



. ff. 



41. T9 



39.05 



2.06 



31.52 



29.66 

 8.79 

 12.15 

 27.80 

 29,86 

 34.19 

 36.50 

 3y.04 

 41.56 

 .01 



n + ^- A < 4" "*' 



Nov. 1,.,, 



2..,, 



O* « « ft 



T - • ft • 

 Oft ft ft ■ 



6ftft •• 



«v«J » « * • 

 op-^C » ft * ft 

 -^rt i ft « « « 



'>7 



f^^ » • « « 



9. 



— 0,802 



— 0.199 

 0.000 

 0.000 



— 0.4II 

 O.IHX) 



0.773 



o.uuo 



0,000 



+ 0.672 

 0.000 



— 4.370 



— 4.270 



45.76 



49,99 

 52.07 



— 54.11 



— 55.17 



— 57.31 



-I- 12 22.04 

 Z 1 29.88 



— 1 32.22 



— 1 a>.09 

 _ 1 37.36 

 + 12 25.83 

 _ 1 42.73 



Tbc valttc ol At aOootea for Oie mean>tiuie 



the coiuplf mciit of the time vaiuo, it becuuies utce.^ ary to cl»ange the eign of (» + c.) 



