Stations. Astronomical
Latitudes.
Distance of
Parallels.
° Ft.
Formentera 38 39 53.17 · ·
Mountjouy 41 21 44.96 982671.04
Barcelona 41 22 47.90 988701.92
Carcassonne 43 12 54.30 1657287.93
Pantheon 48 50 47.98 3710827.13
Dunkirk 51  2  8.41 4509790.84

The distance of the parallels of Dunkirk and Greenwich, deduced from the extension of the triangulation of England into France, in 1862, is 161407.3 ft., which is 3.9 ft. greater than that obtained from Captain Kater’s triangulation, and 3.2 ft. less than the distance calculated by Delambre from General Roy’s triangulation. The following table shows the data of the English arc with the distances in standard feet from Formentera.

° Ft.
Formentera · · · ·
Greenwich 51 28 38.30 4671198.3
Arbury 52 13 26.59 4943837.6
Clifton 53 27 29.50 5394063.4
Kellie Law 56 14 53.60 6413221.7
Stirling 57 27 49.12 6857323.3
Saxavord 60 49 37.21 8086820.7

The latitude assigned in this table to Saxavord is not the directly observed latitude, which is 60° 49′ 38.58″, for there are here a cluster of three points, whose latitudes are astronomically determined; and if we transfer, by means of the geodesic connexion, the latitude of Gerth of Scaw to Saxavord, we get 60° 49′ 36.59″; and if we similarly transfer the latitude of Balta, we get 60° 49′ 36.46″. The mean of these three is that entered in the above table.

For the Indian arc in long. 77° 40′ we have the following data:—

°Ft.
Punnea8931.132· ·
Putchapolliam105942.2761029174.9
Dodagunta125952.1651756562.0
Namthabad15553.5622518376.3
Daumergida18315.2923591788.4
Takalkhera21551.5324697329.5
Kalianpur24711.2625794695.7
Kaliana293048.3227755835.9

The data of the Russian arc (long. 26° 40′) taken from Struve’s work are as below:—

°Ft.
Staro Nekrasovsk45202.94· ·
Vodu-Luy47124.98616529.81
Suprunkovzy48453.041246762.17
Kremenets50549.951737551.48
Byelin52242.162448745.17
Nemesh54394.163400312.63
Jacobstadt56304.974076412.28
Dorpat582247.564762421.43
Hogland6059.845386135.39
Kilpi-maki62385.256317905.67
Torneå654944.577486789.97
Stuor-oivi684058.408530517.90
Fuglenaes704011.239257921.06

From the are measured in Cape Colony by Sir Thomas Maclear in long. 18° 30′, we have