98 | METHOD OF COMPILING THE MAP. 
The meridian which passes ‘‘100 paces west of Fort Smith" forms the west boundary of 
Arkansas between the Arkansas and Red rivers. There being 4’ difference in longitude between 
Lieut. Whipple’s position of Fort Smith and the one adopted by me, the discrepancy has been 
distributed along his route between Fort Smith and the branch of Topofki creek, which is in 
longitude 96° 57’ 37”, this distance being practically enough to reduce the difference within 
the limit of error of such reconnaisance. From this branch of Topofki creek to Albuquerque 
his map is reduced without change. This portion of Lieut. Whipple’s map, forming sheet 
No. 1, as carefully revised by him, does not differ materially in its geographical positions from 
that published in the House Executive document No. 129, Ist session 33d Congress. The 
following changes were made by him in the names: Camp No 31, Washita river, to Camp No. 
31, Comet creek ; Camp No. 32 to Camp No. 32, Silver creek ; Camp No. 33, Washita river, 
to Camp No. 33, Oak creek; Camp No. 42, Antelope creek, to Camp No. 42, White Sandy 
creek. Lieut. Whipple’s یا‎ of Albuquerque, 106° 37’ 52,” is 6’ east of Major pacii 8 
position for it. 
From Albuquerque west to Soda lake Lieut. Whipple’s revision of his work changed the 
longitudes of nearly all his points, as first published in House document No. 129, 1st session 
33d Congress. The first edition of the general map was compiled and engraved from his pre- 
liminary map. The second edition contains his work in its revised form. As Lieut. Whipple’s 
longitudes were, in some instances, determined by means of observations with an astronomical 
transit, his geographical positions were adopted in preference to those of Lieut. Simpson on his 
expedition to the Navajo country in 1849, or of Captain Sitgreaves in his expedition along the 
Zufii and Colorado rivers in 1851. The following is a list of the common points of their routes 
with the different longitudes : 
Simpson. | Sitgreaves. |Whipple's 1st Whipple’s 2d 
map.* _ map. 
ps dit w oi 5$ D 9». 
Oiga مهو‎ 108 41 45 --| 108 19 00 | 108 14 18 
OMEN pet 108 56 00 108 56 00 | 108 32 00 108 42 44 
Last Camp on Colorado Chiquito ....... 110 53 37 110 50 00 110 53 37 
Leroux Spring ..... 111 39 32 | 111 37 00 111 39 32 
113 29 50 | 113 27 00 118 21 21 
Common Point on Colorado, latitude 349 50’ 114 40 00 | 114 30 00 114 29 00 
Mouth of Williams' river | 114 14 00 114 05 00 114 00 00 
The latitudes of these different surveys agree almost exactly. 
The route of Capt. Sitgreaves 
was caben both times - fit the pnm cmt determined by Lieut. Whipple, sometimes requir- 
longa Capt. Sitgreaves’ route down the Colorado, from 
Williams’ river to Fort Yuma, is made to accord with Lieut. Whipple's determination for the 
mouth of Williams' river, and that of the United States Mexican Boundary Commission for Fort 
Yuma.  Lieut. Whipple, in — his sheet No. 2, made the following changes in the names 
of places : 
Camp No. 16, Rio Puerco of the Fü to Camp No. 76, near Lithodendron creek. 
Camp No. 77, Lithodendron creek; to Camp No. TT, Rio Puerco of the West. 
` ® The first edition of the general map app ith these det basis for that part of the 35th parallel route: 
| 
Í 
| 
! 
