206 



ASTRONOMY, 



Eadcliffe observations, in which equal weight is given to the results deduced from the Greenwich 



educed from Phi 

 from the mouth 



High 



so miicli more reliable tlian tliat deduced from Greenwich observations; wherein the law of its 



mot 



estimate 



of any one series^ cannot certainly be a very reliable guide^ unless applied to a continued series 

 of observations, made under various changes of condition^ such as may eliminate all possible 

 or probable errors to which observations are subjected. 



In the results tabulated I have therefore introduced all such as appear reliable, giving to each 

 its estimated value in the final result, without any regard to its ^' probable error/' as it does 



may 



which have been combined in the computations. In adopting 



am 



m 



^self sustained by a paper in the ^^Astronomical Journal/' of January 9, 1856, over the 

 signature of Professor Airy, astronomer royal. 



I have therefore to recommend that, until corrected by the application of more accurate laws 

 of the moon's motion, or additional observations, that 6"^ 28^ 30^5 should continue to be adopted 



tronomical station, west from the meridian 

 Very respectfully, your obedient servant, 



THOM 



Captain TopograpJiical Engineers. 



Major W. H. Emoky, United States Commissioner. 



Note. 



and 



combined in different ways, without, as it appears, materially clianging the result given above. 



1. In table H, showing the results of the moon's limbs separately combined — giving to those results 



their relative values adopted for each night, (as in table G,) the mean of I and 11 limbs being. .- =: 6A.287W,303.52 



2. In table I, showing those results deduced from actual corresponding observations only, and giving 



to those results their relative values adopted for each night, the mean of the whole being - •=. 6A.287W.305.38 



3. In table K, showing the results deduced from actual corresponding observations only, of each limb 



separately combined — giving to those results their relative values adopted for each night— a mean 



of the two limbs bemg -« =6A.287n.30«.45 



.f 



GEORGE THOM, 

 CO'ptam Tbpogra^hical Engineers 



a 



