His Ledger B reveals that as early as 1730 his legal career was becoming firmly established. It records fee accounts, charges for drawing deeds, writing bonds, and representing clients in various courts. In that year he "subscribed to Laws of Virginia" through William Parks, the Williamsburg printer and stationer, and began to build up a substantial law library, which was augmented by the purchase of 40 lawbooks from Robert Beverley.
On October 13, 1730, Mercer obtained title from David Waugh to the Ballard house and lots on the basis of the "Statute for transforming uses into possessions." At the same time he acquired the three lots originally granted to John Waugh, while nine months later he was given the release of the three lots inherited by George Mason from his father.[60] Mercer's foothold in Marlborough was now secure.
Following these developments, he "employed the County Surveyor to lay off the several Lots he had purchased," which led to the discovery of the previously mentioned disparities and conflicts between the Buckner survey of 1691 and the missing Gregg survey of 1707. For some reason the town now lacked feoffees, so Mercer "applied to the County Court of Stafford on the tenth day of June one thousand seven hundred and thirty-one and the said Court then appointed Henry Fitzhugh Esquire and James Markham Gent. Feofees of the said Town." Mercer stated that he "proposed making great Improvements ... and wanted to take up several other Lots to build on." The court thereupon ordered John Savage, the county surveyor, to make a new survey, "having regard to the Buildings and Improvements then standing"--a significant instruction, intended no doubt to permit the reconciling of conflicting titles with respect to what actually was built.[61]
The new survey was laid out July 23, 1731, "in the presence of the said Feoffees," and drawn with the same plan and numbering as Buckner's, except that an additional row of lots was applied along the western border of the town, compressing slightly the former lots as planned by Buckner and pushing them eastward (fig. 2). This extra row, we have reason to believe, was added with "regard to the Buildings and Improvements then standing."