Memorandum from Benjamin H. Latrobe
Mr. Latrobe presents his respectful Compliments to the President of the U. States:
In preparing for his survey of the line of Potowmac Canal, Mr L. has obtained access to the records of the Commissioners, which happen to be perfect as to the levels of the Streets N. West of the Presidents house, & South of the large Street K and also as to those of some streets about the Capitol. The page marked by this letter (32) exhibits the level above high water of that part of the Pennsylvania Avenue which is immediately in front of the six buildings. It appears that the level on the highest point marked * is 76 feet 10.i 9.10 above high water. Should the Canal be carried along this line there will of course be a difference between the level of the street & of the Water of 44 feet (the fall at the locks being only 32.f 6i or thereabouts.) This difference will Mr. L. fears, be fatal to the idea of carrying the Canal along the line of the Pennsylvania Avenue,—for a navigable tunnel from Rock Creek to the descent of the hill East of the President’s house would be cheaper than such an open Canal.
As there is lower Ground both to the right & left of the Pennsylvania Avenue Mr L. examined the book as to a variety of Streets running across or along the lowest situations, & finds that there is not any track between the Pennsylvania Avenue & the high Ground intended for the University, which is lower than from 50 to 54 feet above high Water,—giving a difference between the level of the Streets & of the Water in the Canal of at least 20 feet.—From the bank of the Rocky Creek, North of the Pensylvanian Avenue towards the Tiber, the hollow, (which appears to run along the Wide street marked K, & then to follow the Massachusets Avenue to the Tiber) does not seem lower for a very considerable part of its extent than that between the Pennsylvania Avenue and the University hill, so that no advantage would be gained by leading the Canal into that “uninteresting” part of the City, as the natural level of the Ground must be about 50 feet above high Water. Of the levels of the streets in this direction Mr L could not find any record in the office of the City surveyor.
It appears1 from these facts that if the Canal be made not very different in its level from that of the street, the streets near the river must be resorted to. The line indeed of the Cut will be circuitous, & the Ground often disadvantageous,—but the thing is practicable;—and its execution might perhaps be attended with the advantage of unloading the Country produce near to the Stores from which it must be exported, & which will naturally arrange themselves near the Potawmac.—As the weather forbids operations in the open Air, Mr Latrobe will employ himself in making the drawings of the dock & Locks, untill he receives further instructions from the President, upon whom he will wait at the first convenient moment.—
Secretary’s office P.U.S
Monday morning [22 Nov. 1802]
Mr. N. King is in possession of an accurate detailed plan, & sections of Georgetown, from Fayette street to Rocky Green, which will render Mr Ls. operation through that City unnecessary.—Indeed there does not appear to be more than one weeks surveying necessary to obtain all the requisite data for a very detailed estimate.—
MS (DLC); entirely in Latrobe’s hand; partially dated; endorsed by TJ as a document of 22 Nov.
For the residences at Pennsylvania Avenue and 22d Street known as the six buildings, see Vol. 33:595n.
The detailed plan of Georgetown, from surveys by Nicholas King in 1800, included street gradations and other details (Latrobe, Correspondence description begins John C. Van Horne and Lee W. Formwalt, eds., The Correspondence and Miscellaneous Papers of Benjamin Henry Latrobe, New Haven, 1984-88, 3 vols. description ends , 1:231–2n).
1. MS: “It is appears.”