Lengths and Levels
to
BRADSHAW’S MAPS
of
THE CANALS,
NAVIGABLE RIVERS,
and
RAILWAYS,
in the
PRINCIPAL PART OF ENGLAND.
dedicated to
THOMAS TELFORD, F.R.S. L. & E.
President of the Institution of Civil Engineers.
DATUM, SIX FEET TEN INCHES UNDER THE SILL OF THE OLD DOCK GATES AT LIVERPOOL.
London:
PRINTED BY E. RUFF, 2, HIND COURT, FLEET STREET.
1833.
Explanation.
In submitting the Series of Levels which have been taken for this Work, it may be necessary to give some explanation of the plan pursued, and of its general utility to the public. I have taken 6 feet 10 inches below the sill of the Old Dock Gates at Liverpool for my standard; and on the lines of Navigation and Railway, is marked, in Feet and Inches, the height that such parts are above that standard. By this means the comparative elevation of the county, whether upon the same or different lines of Navigation or Railway, can be readily ascertained.
This information will be found of the greatest importance to those who are interested in the union, or extension of the present Canals, Railways, or Turnpike Roads; and it is also hoped that it will be useful to the Legislator, the Man of Science, and an excellent reference to Public Companies, and individual Share Holders.
By levelling along the Grand Junction and Regent’s Canals, I have been enabled to connect these levels with those taken by Captain Lloyd, from Sheerness to London Bridge.