192 



ASTRONOMY. 



aK San Elceano.— 'Moon culminations were observed at tliis place simultaneous witli those 

 observed at Frontera. These observations extend through a period of five lunations, com- 



makinc^j as combined in table (II,) 



tude of San Elceario=7 



This result, however, as well as that above given for Frontera, has been corrected by com- 

 bining with them the difference of longitude of these places, as determin.d by flashes of gun- 

 powder simultaneously observed at Frontera, El Paso del Norte, and San Elceario, on the 

 nights of February 14, 18, 19, and March 14, 1852, (see table III,) by which it appears that 

 San Elceario is east of Frontera=l'" T'.SO, whilst that deduced from moon culminations, 



1'° 8^59 ; difference,=r.29. 



The longitudes of Frontera and 

 corrected by half the difference -^ 

 San Elceario, T S"" 5^07. 



h. El Paso del Norte beii 



in longitude=r 5" 56^43 -^ 

 c. The astronomical stati 



from 



r 6"-12\37; 



Cj 



/ 



Norte, is in longitude^T" 2™ 29\06 ; having been determined, in the absence of moon culmina- 

 tions , by thirteen flashes of gunpowder, simultaneously observed at that station and San Elceario, 

 on the night of June 21, 1852, to be 2" 36\0 east of San Elceario.— (See table IV.) 



Norte 



was determined by a series of moon culminations, observed during a period of two lunations, com- 



5Y"39'.02 



west of the meridian of G-reenwich. — (See table V.) 



gh 42- l\78 



Fort Duncan, Texas, was determined to be in longitude 

 Greenwich, from observed moon culminations, commencin 



or 



October 19, and ending October 27, 1852, combined as per table herewith marked VI. 



/■ 



m 



moon 



mo n til 



mar 



g. The longitude of the astronomical station near the mouth of the Bio Bravo del Norte has 

 already "been discussed by me, as presented to you in report of February 19, 1856, (herewith ap- 

 pended, marked g,) to which I refer you for the conclusion of the subject of the longitudes of the 

 primary points on the Kio Bravo ; it explains in detail the manner in which all the observations 

 and computations have been tabulated, for which reason I have not herein before made reference 

 thereto. 



II. Latitudes. 



The two volumes herewith* (marked Latitudes^) contain, in a tabulated form, all the individual 

 observations made by yourself with the zenith instrument, for determining the latitudes of all 

 the primary astronomical stations on and near the Eio Bravo del Norte, from Frontera down to 

 its mouth, wnth the exception of San Elceario and Fort Duncan ; of these two, the former was 



Whipple 



Michler 



meridian 



* To be deposited in the Departnieat of the Interior. 



