In this great work he had the co-operation of Major Skinner and of Captain Gallwey, and to these two gentlemen the public are indebted for the greater portion of the field-work and the trigonometrical operations.

To judge of the difficulties which beset such an undertaking, it must be borne in mind that till very recently travelling in the interior of Ceylon was all but impracticable, in a country unopened even by bridle roads, across unbridged rivers, over mountains never trod by the foot of a European, and amidst precipices inaccessible to all but the most courageous and prudent.

Add to this that the country is densely covered with forest and jungle, with trees a hundred feet high, from which here and there the branches had to be cleared to obtain a sight of the signal stations.

The triangulation was carried on amidst privations, discomfort, and pestilence, which frequently prostrated the whole party, and forced their attendants to desert them rather than encounter such hardships and peril.

The materials collected by the colleagues of General Fraser under these discouragements have been worked up by him with consummate skill and perseverance.