682 [=43] (V.2)

682

[note in left margin:

33 - [C, struck through] D. - Vol ii.
Part iii. Ch. i
Wiltshier]

upon which the brick work was
raised and allowed to indurate
previously to the commencement
of undersinking operations. On
the completion of undersinking the
interior hollows or wells were filled
either with clay or sand, the latter
being preferred, if available; in
this state they were allowed to
stand, ^for as long a period as possible,
so as to admit of settlement: the
wells were then arched over, and
the mass was ready to receive the
superstructure. This plan of oper-
-ations applies to all the blocks,
each of which was subjected to
the same process. On the lines of
revetment the space left between
each pair of blocks (to prevent col-
-lision in sinking) was equal
to from 1 1/2 to 2 1/2 and that between the
larger blocks as in the bridge was
2 feet. This [?] space is arched
and ^in some cases has been merely
bricked over previously to the
raising of the superstructure.
Both in front and rear it is filled
by piling driven to a depth of
20 feet, so as ^[to expose] as far as possible,
[to form, struck through] an unbroken face either
to the action of the current in front,
or to the thrust of the earth in its
rear.

The revetment ^walls both on the
right and left, are on the same
design, they offer a curved front
to the canal, and are strengthened
by counterforts [to the rear, struck through]. On
the line connected with the
underdrainage this wall is
still further strengthened by the
masonry.

682

[note in left margin:

33 - [C, struck through] D. - Vol ii.
Part iii. Ch. i
Wiltshier]

upon which the brick work was
raised and allowed to indurate
previously to the commencement
of undersinking operations. On
the completion of undersinking the
interior hollows or wells were filled
either with clay or sand, the latter
being preferred, if available; in
this state they were allowed to
stand, ^for as long a period as possible,
so as to admit of settlement: the
wells were then arched over, and
the mass was ready to receive the
superstructure. This plan of oper-
-ations applies to all the blocks,
each of which was subjected to
the same process. On the lines of
revetment the space left between
each pair of blocks (to prevent col-
-lision in sinking) was equal
to from 1 1/2 to 2 1/2 and that between the
larger blocks as in the bridge was
2 feet. This [?] space is arched
and ^in some cases has been merely
bricked over previously to the
raising of the superstructure.
Both in front and rear it is filled
by piling driven to a depth of