OF THE SUN, JUNE 16, 1806. 277 



"59 to 57 and returned after the eclipse nearly to its former 

 " position." 



I shall now proceed to give you the supplementary remarks 

 which have been furnished by Professor Cleaveland. 



" Our large reflecting telescope has the magnifying power of 

 " 450. I used the shortest eye-glass and middle-sized specu- 

 " lum, which, if I am correct, magnifies 360 times. 



"The President used his own telescope, and left the ma- 

 " nagement of the large one to myself. — Its magnifying pow- 

 " er is so great, that fearing lest I should not discover the com- 

 « mencement of the eclipse, I kept the telescope in a slow mo- 

 " tion, ranging backwards and forwards in a small arc. The 

 "telescope was probably at one extremity of this arc, while 

 " the immersion actually took place, for at the moment when 

 " it was actually discovered by the telescope belonging to the 

 "equatorial, I moved my telescope, and found the shadow 

 " must have been discoverable two seconds at least. I allowed 

 «« one second for the motion of the telescope, after the eclipse 

 " was seen by the observer with the equatorial, and the time 

 " of the commencement was noted one second back accord- 

 " ingly. This perfectly agreed with the observation of the 

 " emersion. — We had some one at the clock, counting seconds; 

 " and the shadow was visible one second longer by the large 

 " telescope, than by the other, which circumstance was con- 

 " sidered confirmatory of the allowance of one second made at 

 " the commencement." So far the college observations extend. 



I do not recollect to have heard of any accurate astronomi- 

 cal observations, made in the United States to the north of 

 Brunswick. 



No! XLV. 



On finding the longitude from the mootis meridian altitude, by 

 William Dunbar of Natchez. 



Read August 15th, 1806. 



THE usual mode of making the lunar observation for the 

 purpose of ascertaining the longitude, requires the aid of a 



