The overall relevance of this survey can be seen when set against the change in leadership of the British army when Sir Henry Clinton replaced Sir William Howe in May 1778 and immediately shifted the focus of British strategic emphasis away from New York and New England to the southern colonies.  The British, as part of their ‘Southern Strategy’ had already decided by the time this chart was produced that the largely loyalist middle and southern states might still be retained as part of the Empire.  By occupying key towns such as Savannah in Georgia and Charleston in South Carolina and mobilizing and arming the loyalist population, including slaves, they hoped to achieve four things:  1. They may be able to split these states from the rest;  2. The more loyalists that could be assimilated into the army the more British troops could be concentrated elsewhere;   3. They might yet retain financial control - apart from anything else these middle states produced the commodities upon which the economics of Empire was built - tobacco, rice, indigo and so on;  4. They may yet link these states along with their holdings in east Florida, the Bahamas and Bermuda as a new colonial grouping to compensate for the loss of the New England states. 

It is worth noting that at this time Washington as a city did not exist but now stands just above Alexandria which is marked at 39 degrees 10' on the Western edge of the chart.  Yorktown, the scene of what was in September and October 1781 the final and decisive battle of the war where on 19th October Lt-General Charles, Earl of Cornwallis surrendered and effectively ended the war is marked simply as York.  On a point of accuracy this chart places ' York' at 35.08, 77.40 whereas our modern day Satellite technology places the town at: 37.23, 76.50.