James's Account of S. H. Long's Expedition, 1819-1820, part 4 - Edwin James; Stephen H. Long; Thomas Say

{xli} Allowance to be made for error and variation of watch. Longitude by account, 6^h 26´ W.

Longitude deduced, 6^h 26´ 12˝, or 96° 33´ 00˝ W. of Greenwich.

*Camp on the Canadian river, fifteen miles above its mouth.*
Sept. 9, 1820.	Meridian double altitude of sun's lower limb	120° 13´ 00˝
Index error - 4'. Lat. deduced	34 50 15 N.

*Observations made on the Arkansa river, at Fort Smith, Belle Point,situated at the confluence of the Arkansa and Poteau rivers.*
Sept. 14, 1820.	Meridian double altitude of sun's lower limb	116° 22´ 00˝
Sept. 14, 1820.	Index error - 4´. Latitude deduced	34 51 07 N.
Sept. 15, 1820.	Meridian double altitude of sun's lower limb	115 36 00
Sept. 15, 1820.	Index error - 4´. Latitude deduced	34 51 00 N.
Sept. 16, 1820.	Meridian double altitude of sun's lower limb	114 50 30
Sept. 16, 1820.	Index error - 4´. Latitude deduced	34 50 35 N.
	Mean latitude of Belle Point	34 50 54 N.

*Equal altitudes of Sun to find error of watch, at noon.*
	Time from Noon, A.M.	Time from Noon, P.M.	Error of Watch.
Sept. 15, 1820.	3^h 41´ 21˝	3^h 36´ 32˝	2´ 47˝ fast. Mean time.
3 38 35	3 33 46

	Time per Watch, P.M.	Distance of Sun and Moon.	Index error.
Sept. 15, 1820.	3^h 55´ 46˝	93° 59´ 30˝	- 4´

Allowance for error of watch as usual. Longitude by account, 6^h 18´ west of Greenwich.

Longitude of Belle Point deduced from the foregoing data, 6^h 17´ 24˝, or 94° 21´ 00˝ west of Greenwich.