It is now no longer a secret where Mr. Howe's fleet is. We have authentic intelligence that it is arrived at the head of Chesapeake Bay, above the river Patapsco, upon which the town of Baltimore stands. I wish I could describe to you the geography of this country, so as to give you an adequate idea of the situation of the two great bays of Chesapeake and Delaware, because it would enable you to form a conjecture concerning the object he aims at. The distance across land from the heads of these bays is but small, and forms an isthmus, below which is a large peninsula, comprehending the counties of Accomac and Northampton in Virginia, the counties of Somerset and Worcester in Maryland, and the counties of Kent and Sussex in Delaware. His march by land to Philadelphia may be about sixty or seventy miles. I think there can be no doubt that he aims at this place, and he has taken this voyage of six weeks, long enough to have gone to London, merely to avoid an army in his rear. He found he could not march this way from Somerset Court House without leaving General Washington in his rear. We have called out the militia of Virginia, Maryland, Delaware, and Pennsylvania to oppose him, and General Washington is handy enough to meet him; and as General Washington saved Philadelphia last winter by crossing the Delaware and marching to Morristown and so getting in the rear of Howe, so, I conjecture, he will still find means to get in his rear between him and Chesapeake Bay. You may now sit under your own vine and have none to make you afraid. I sent off my man and horse at an unlucky time, but if we should be obliged to remove from hence, we shall not go far. If Congress had deliberated and debated a month, they could not have concerted a plan for Mr. Howe more to our advantage than that which he has adopted. He gives us an opportunity of exerting the strength of all the middle States against him, while New York and New England are destroying Burgoyne. Now is the time! Never was so good an opportunity for my countrymen to turn out and crush that vaporing, blustering bully to atoms. 201. JOHN ADAMS. Philadelphia, Saturday, 23 August, 1777, 4 o'clock.