274 WOODEN WATER-PIPES AT CLERKENWELL, LONDON.
knowledge of their existence rather than intending to convey
the impression that they were uncovered.
It becomes necessary to consider whether any advantage
would be gained by leaving these pipes open, and on this point
the account given by Matthews in Hydraulia3 is instructive.
[The author then proceeds to give the extracts embodied in
Mr. Holmes' paper ante pp. 230-1, to which our readers are
referred.—Ed.]
Such a state of things as there described makes it extremely
probable that the expense of time, labour, water, and inconveni-
ence in having to excavate covered pipes in order to discover
a leakage, would far have exceeded the greater liability to decay
and damage, when the pipes were exposed.
The ease with which defects could be discovered when they
were uncovered is strikingly shown in the second view.
Elm also, of which most of these pipes were made, is the
wood best adapted to stand changes of wet and dry conditions.
It must be remembered, also, that damage from frost would be
far less considerable than with metal pipes. At points such as
the bridge, from whence the graceful fountains are issuing
(View 2), no covering sufficient to form much protection would
seem to be possible.
The formation and renewal of these pipes appears to have
been a far less difficult matter than has been supposed by
modern engineers. In a footnote in Hydraulia we are told that
the New River Company had a spacious wharf on the Thames at
the bottom of Dorset Street, Salisbury Square, for landing timber
and commodious shops for boring pipes, etc.
All things considered it seems probable, therefore, that in the
open fields around London these wooden water-mains were
actually uncovered as shown in the drawings.
3 Hydraulia, or Mode of Supplying London with Wider. W. Matthews, 1841, p. 66.