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Benjamin Banker and the Survey of District of Colombia, 1791


Quiz Questions

1.Benjamin Banker He was, in fact, the scientific assistant of the surveyor, Major Andrew Ellicott, and his work was limited to making astronomical observations and calculations with Ellicott’s instruments maintained in the field camp, for the period of the first three months of the project.
True
False
2. It may have been George Ellicott who reminded the Major Andrew Ellicott about Benjamin Banneker, who lived near the Mills and had recently ____________ astronomy and also calculated an ephemeris.
Taught himself in
Learned from him
3. When Banneker accepted Major Ellicott offer it was the first time he had ventured more than __________ miles from his farm.
10 miles
20 miles
100 miles
4. This is a
PDH Course - Benjamin Banker and the Survey of District of Colombia, 1791 1
Large Zenith Sector made by David Rittenhouse for Andrew Ellicott and used in the survey of the District of Columbia
Camera stand for taking pictures in 1801
5.The purpose of Zenith sector was to observe meridional observations.
True
False
6. Observations were made of about ________________ crossing the meridian at different times during the night and the observations were repeated a number of times.
a half dozen different stars
North star
7.

Ellicott had commented that when stars were so near the zenith they were affected by the different refractive powers of the atmosphere which derived from the varying degrees of density.

True
False
8. He found that the error of the visual axis could be completely corrected by taking
The measurements from north and south.
the zenith distances of the stars with the plane or face, of the instrument both east and west.
9.This is
PDH Course - Benjamin Banker and the Survey of District of Colombia, 1791 2
Transit and Equal Altitude Instrument used by Andrew Ellicott in the survey of the District of Columbia
A zenith sector used by Ellicot
10.This is
PDH Course - Benjamin Banker and the Survey of District of Colombia, 1791 3

Plain Surveying Compass made by Benjamin Rittenhouse for Andrew Ellicott and used in the survey of the District of Columbia
Andrew Elliccot’s pocket watch.
11.This is
PDH Course - Benjamin Banker and the Survey of District of Colombia, 1791 4
Tripod camera stand in 1801
Small Zenith Sector used in the survey of the District of Columbia
12.Considerable confusion developed among subsequent writers concerning the relative roles of Ellicott, L’Enfant and Banneker in the survey of the Federal City. Ellicott was, contrary to popular misconception, the first to receive an appointment to the project. His assignment was specifically to produce a survey of a ten-mile square within which the national capital was to be designed and laid out by L’Enfant. Ellicott and L’Enfant each worked independently under the supervision of the Commissioners appointed by Washington. After L’Enfant’s subsequent dismissal, Ellicott was assigned the dual responsibility for continuing L’Enfant’s work on the design of the city, and layout of public buildings, streets and property lots, in addition to completing his survey. Banneker was employed directly by Ellicott and did not at any time, as far as can be determined, work with or for L’Enfant.
True
False
13.This is
PDH Course - Benjamin Banker and the Survey of District of Colombia, 1791 5
Small telescope for stargazing
Portable Quadrant for field use, owned by Andrew Ellicott