At this period the English ministry adopted the aggressive policy already mentioned in connection with the French and Indian war, indicative of a determination to contest with France the right to occupy the interior of the continent. This policy had been inaugurated by Virginia with the express purpose of stimulating the adoption of a similar policy by North Carolina and Pennsylvania. Two land companies, organized almost simultaneously, actively promoted the preliminaries necessary to settlement, despatching parties under expert leadership to discover the passes through the mountains and to locate the best land in the trans-Alleghany. In June, 1749, a great corporation, the Loyal Land Company of Virginia, received a grant of eight hundred thousand acres above the North Carolina line and west of the mountains. Dr. Thomas Walker, an expert surveyor, who in company with several other gentlemen had made a tour of exploration through eastern Tennessee and the Holston region in 1748, was chosen as the agent of this company. Starting from his home in Albemarle County, Virginia, March 6, 1750, accompanied by five stalwart pioneers, Walker made a tour of exploration to the westward, being absent four months and one week. On this journey, which carried the party as far west as the Rockcastle River (May 11th) and as far north as the present Paintsville, Kentucky, they named many natural objects, such as mountains and rivers, after members of the party. Their two principal achievements were the erection of the first house built by white men between the Cumberland Mountains and the Ohio River--a feat, however, which led to no important developments; and the discovery of the wonderful gap in the Alleghanies to which Walker gave the name Cumberland, in honor of the ruthless conqueror at Culloden, the "bloody duke."