C 486 n 
XXVJI. An abstract of the results deduced from the measurement 
of an arc on the meridian , extending from latitude 8° 9' 38", 4, to 
latitude 18 0 3' 23", 6, TV. being an amplitude of 9 0 53' 45", 2. 
By Colonel William Lambton, F, R. S. 33d Regiment 
of foot . 
Read May 21, 1818. 
In the 12th vol. of the Asiatick Researches, there are detailed 
accounts of two complete sections of an arc on the meridian, 
measured by me at different times, in prosecuting the trigo- 
nometrical survey of the Peninsula of India. The first is 
comprehended between the parallels of Punnae, a station near 
Cape Comorin, in latitude 8*9' 38^,39, and Patchipolliam in 
Coimbefoor, in latitude io° 59' 48^,93 ; being an amplitude 
of 2° 50' 10", 54. The second is comprehended between the 
parallels of Patchipolliam and Namthabad, a station near 
Gooty, in the ceded districts ; and lying in latitude 15 0 6' o",2i, 
gives an amplitude of 4°6' 11", 28. Since these measure- 
ments were made, I have had the good fortune to get another 
section, extending from Namthabad to Daumergidda, in the 
Nizam's dominions, which being in latitude 18 0 3' 23", 6, 
gives an increase of 2 0 57' 23", 32 ; making in the whole an 
arc of 9 0 53' 45", 14 in amplitude ; the longest single arc that 
has ever been measured on the surface of this globe. The 
detailed accounts of this last arc, with various conclusions 
concerning the three sections, have been presented to the 
Asiatick Society by the Marquess of Hastings, the present 
Governor General, and will be published in the 13th volume 
