This section of the map shows how close the line came to intersecting the Potomac River at the site of present-day Hancock, Maryland. The river lies just two miles below the boundary line at this point. Note that "Conoloway" is now known as "Tonoloway" and "North Mountain," shown just to the east of Licking Creek, appears under different names on modern maps.

Since the Potomac was Maryland's southern boundary, the possibility that his colony might be truncated by the survey was of some concern to the proprietor.

Documents

Lord Calvert to Governor Sharpe, letter dated January 1, 1754

***
His Lordps desires you will obtain Mr Cresapes Opinion Certain by Observation of the North Temporary Line. His Majesty's Line by advice of his Council bet: Maryland & Pensilvania, of wh Line I Learn Mr Cresap thinks is North of the highest Bend & Flow of Potomack River. If the Bend is over the Line the Pensilvanians will claim Water Passage to the Spring Head & on that River; it is of Consequence to know upon Settlg the North Temporary Line.

***

***
As there are no Bills yet framed & nothing at present dependig between the Houses of any Consequence, I propose to leave them for a few Days & to be at the Meeting of the Commissioners at York Town the 16th Inst where Messrs Mason & Dixon are to attend us. I have not for some time received any Letter from these Gentlemen but am informed by some who have been with them on the Line that having continued it so far as North Mountain they desisted about a fortnight ago in order to take an Observation at that place, The Line they have now described has it seems crossed or intersected the Temporary Line several Times & the Spot where they broke off is supposed to be about half a Mile Southward of what was reputed to be the Temporary Line in that part of the Country for the Temporary Line was not you know ever continued so far Westward. Capt Shelby who lives near the North Mountain & went with Messrs Mason & Dixon to the Top of it in order to view the Course of the Potowmack says they assured him the Line when continued will not any where intersect that River & that they apprehended it would run at least eight or ten Miles to the Northward of Fort Cumberland.

***

From the C&O Canal Company's 1832
"memorial" to the Maryland legislature:

This line of canal will pass through the town of Hancock, in Maryland, at the distance of six miles from that of Bath, in Virginia [Berkeley Springs], where it will come in contact with the artificial road between Baltimore and Wheeling ... The traveller from the west, after crossing the Allegany, will enter a packet boat at Hancock, propeeled, as those on the Ardrossan canal of Scotland, at the rate of nine or ten miles an hour, and reach Washington in a single day of comparative rest.

Text Sources:

• Sharpe/Calvert correspondence is from Volumes 6 and 14 of the Archives of Maryland, Correspondence of Governor Horatio Sharpe, William Hand Browne, Maryland Historical Society, Baltimore, 1895. [On-line at Maryland State Archives]
• "The memorial of the Chesapeake and Ohio Canal Company to the General Assembly of Maryland," reprinted in Memorial of the Corporation of the City of Washington, Remonstrating Against the Surrender to the State of Maryland of the stock held by that Corporation in the Chesapeake and Ohio Canal, March 11, 1840, printed by Blair and Reeves. [The location of the dam above Cumberland is discussed on page 47.]