[85] Ledger G (original at Bucks County Historical Society) covers the period 1744-1750, with some entries in 1751 and a few summary accounts covering Mercer's career. Further footnoted references to this ledger will be omitted. Charles Carter lived at "Cleve" in King George County, near Port Royal, fronting on the Rappahannock. See FAIRFAX HARRISON, "The Will of Charles Carter of Cleve," _VHM_ (Richmond, 1923), vol. 31, pp. 42-43. [86] Sydenham & Hodgson was a London mercantile firm, represented in Virginia by Jonathan Sydenham. Mercer identified the firm in Ledger G as "Merchants King George" and noted in his journal on January 20, 1745, that he visited at "Mr. Sydenham's." In 1757 the two men were referred to elsewhere as "Messrs. Sydenham & Hodgson of London." See "Proceedings of the Virginia Committee of Correspondence, 1759-67," _VHM_ (Richmond, 1905), vol. 12, pp. 2-4. [87] Extensive research has been conducted by Colonial Williamsburg, Inc., on the forms of vehicles used by such Virginians as Mercer and his contemporaries. TOBACCO CASK BRANDS Hogsheads and casks of tobacco were branded with the symbols or initials of the original owners. Many of the brands are recorded explicitly in the ledger. Mercer, at the beginning of his career, used a symbol M. As his plantations multiplied, however, three symbols were adopted, based on his own two initials. Tobacco casks from Bull Run were marked I^[B.]M. Those from Sumner's Quarters bore the brand I^[S.]M, while the "Home Plantation" at Marlborough had casks marked I^[C.]M (fig. 8). The interpretation of these symbols warrants some digression. In the 17th century, and indeed in the 18th century also, the triangular cipher to indicate the initials of man and wife was commonly used to mark silver, pewter, china, delftware, linens, and other objects needing owners' identifications. The common surname initial was placed at the top, the husband's first-name initial at the lower left, and the wife's at the lower right. This arrangement was used consistently in the 17th century. In the 18th century, however, variations began to appear in the colonies, although not, apparently, in England. Silver made in New York and Philadelphia during the 1700's presents the initials reading from left to right, with the husband's at the lower left, the wife's at top center, and the surname initial at the lower right. The large keystone of the Carlyle house in Alexandria, built in 1751, bears a triangular arrangement of John and Sarah Carlyle's initials: J^[S.]C.[88]