foundations,
wells, etc., and while his studies have been especially influenced by
his views on the formative causes of the present outline of Manhattan
Island (see Section on Waterways, p. no), his researches are
interesting. They confirm, however, all previous impressions as to the
rock basement of the city, as being gneissoid, schistose, and granitic,
with peripheral beddings and interior fillings of sand, gravel and
clay, and the presence of limestone areas, north and, perhaps, also
eastward. They have, however, also furnished suggestive and instructive
outlines of the contour of the underlying rock, and shown its
irregularity, its folded, creased, and channelled surfaces. These
results are referred to more at length under Water-ways (p. no) and the
Evidences of Glaciation in and About Greater New York (p. 190). The
Section of the Rock Basement of Manhattan along the line of Broadway
from the Battery to 33d Street, presented as Map I, is reproduced from
Professor Hobbs' pamphlet.
TOPOGRAPHICAL RETROSPECT*
In
the map of T. Maerfchalckm (1763) the Negro Burial Ground was around
Collect Pond, just north of the Common (the present City Hall Park), on
which stood the Poor House and Powder House, and by the side of which,
as a prolongation of Nassau Street, the Highroad to Boston ran through
Chatham Street to Chatham Square, and thence followed the Bowery.
The
Battery was formerly an elevated section, and is referred to in early
records as a bluff, the land between Trinity Church and the present
Bowling Green being somewhat raised, fronting the Hudson as a receding
bank.
Governor's
Island, which was originally a perquisite of the Director-General, and
formerly known as Nutten Island, was at an early day so extended
towards Red Hook on Long
♦For
most of the material in this section I am indebted to the admirable and
unique papers, letters, sketches, etc., of D. T. Valentine, in the
Manual of the Common Council of New York.
