59 8 The Smithsonian Institution 



tered into the Coast Survey campaign as if it were his own. 

 The steps of the program determined the longitudes. 



H. M. S. 



I. Greenwich-Foilhommerum (Ireland) o 41 33.29 



II. Foilhommerum-Heart's Content (cable) .... 2 51 56.54 

 III. Heart's Content-Calais (Maine) o 55 37.72 



Greenwich-Calais 4 29 7.55 



or, after correcting for a slight error first pointed out by Dr. 

 A. Wagner, 1 the result is 



H. M. S. 



Greenwich-Calais 4 29 7.62 



The numbers given above are the result of observations at 

 five stations, and by the observers Dunkin and others (at 

 Greenwich), Gould and Morgan (Foilhommerum), Dean and 

 Goodfellow (Heart's Content), Davidson and Chandler (Ca- 

 lais), Boutelle (Calais). It was not possible to eliminate the 

 personal equations of these observers by interchanging sta- 

 tions, and the observations for determining the corrections 

 on this account lead to quite anomalous results, entirely at 

 variance with the past experience of the observers. 



The personal equations actually employed in the reductions 

 were obtained by assuming them to have such values as bring 

 the various steps of the program into the best accordance. 

 In the table below, column A gives the personal equations as 

 determined by observation, while column B gives the values 

 actually employed in the reductions : 



A B 



Observed. Adopted. 



s. s. 



Gould-Mosman +<M5 +0.02 



Dean-Mosman +0.12 +o.n 



Goodfellow-Dean +0.03 4-0.02 



Boutelle-Goodfellow 0.13 0.14 



Boutelle-Chandler 0.22 0.04 



Dunkin-Gould unknown. unknown. 



1 Vierteljahrschrift der Astronomischen Gesellschaft, 1871, page 136. 



