AMERICAN’ 
JOURNAL OF SCIENCE AND ARTS. 
[SECOND SERIES.] 
ay 
Arr. ‘Took Ow a New»Method of recording differences of North 
Polar Dista istance or Decknation by Electro-magnetism’; by 
Prof. O. M. Mrrcnet, Director of the Cincinnati Observa 
I wave hertitofor’ declined jubbiohiing any. ; ccount of 
the new methods of astronomical observation in use at the Cin- 
cinnati Observatory, partly because the subject was constantly 
developing by new experiments, and partly because at the New 
Haven meeting of the American Association for the Advance- 
ment of Science, this subject, at my request, was referred to a 
committee for examination. The report of this committee. hav- 
ing now been made, and the whole subject having assumed (by 
another year’s examination and experiment) a more definite and 
positive form, it is now proper to present some general features 
of this new method, some results already reached, and the prob- 
able Se A which remain to be made when suitable natatt 
ments e been provided for the. 
- Observers a well aware of the difference ‘heinoin chats 
tions for Right Ascension and Declination. In the first, the prin- 
ciple of repetition has been extensively introduced with the: best 
results, while as to the other, reliance is mainly placed on the aecu- 
racy of a single bisection of the star observed on one declination 
wire. More than two years since a plan had been: executed by 
myself, and applied to practice in the Cincinnati : 
Sxconp Sertzs, Vol. x1, No. 37.—Jan., 1852. 
