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Show 802 APPENDIX B.- GEOGRAPHICAL POSITION. Allowing the entire change of the first day to be due to No. 1961, and taking the longitudes of the termini, as stated above, The arerage rate of gain lor chronometer No. 1681, daily, b..... 8.031 Arerage rate at beginning and end of journey..*, 7.019 At Fort LeaTenworth. .'. ., 10.000 At Great Salt Lake City. ~... 4.., *.•.....„ ., *„.,.. 4.020 b. m. •. Time by sextant observations at Great 8alt Lake City...* ..... 7 40 48 " " " Fort Leavenworth................. 6 28 81 Difference chronometer time. 1 21 12 , * « in mean time by assumed longitudes. ...>. ......... *.... t.. 1* 09 17,1 Chronometric gain '. * 11 54.9 Time by sextant © beerrailone at Fort Laramie 7 17 29 The number of days between the respective observations, wa » , from Leavenworth'to Laramie, fifty days; thence to Great Salt ' Lake'City, thirty- nine days. The proportion of gpin is therefore 6 min. 41,6 sec, and 5 min. 13.3 sec. Making these corrections) and converting into siderial time, the longitude of Laramie will be given at 105° 19' 50". But taking the rate at the termination of the journey, and applying it to the time given at Laramie, we have, Longitude, Great Salt Lake. 112° 06' 08" . " Laramie 104° 40* 86" This would agree better with that of Fremont in 1842; but he observes in his book of 1843, that the longitudes of that year ate thrown too far west collectively, and proposes to correct, at Fm-taine qui Bouit: taking the amount of correction given at that station in 1845, at 15' 49", his observations place Laramie in 104° 31' 64", which is nearly that adopted in the accompanying map, ' resulting from measured distances and observations, on the homeward journey. Relying upon the accuracy of the map of .1845, we have checked the work made up from course and distance, measured by ati odometer; e « t the crossing of the North Fork of the Platte, and reduced the longitude of Camp 32 on Chugwater, at 104° 56' 45". The chronometric difference of this camp and Laramie is* taken, on account of the good apparent work of the time- keepers and the ' Winding of the road, at 25' 19", which gives the longitude of Fort Laramie at 104* 81' 26". Thence to Fort Leavenworth the intermediate points where latitudes were taken, we make up from course and distance as before. The lunars taken at Laramie and in the Salt Lake Vtelley, are |