New-York tribune., 1899-02-27
THE WEAKNESS or WOODEN DRYDocKs

THE WEAKNESS or WOODEN DRYDOCKS
II the inherent lack of strength in timber
drydocks were as well known as it should be
there would have been long since popular
outcry against their construction for National
use. These dangerous structures have been
foisted upon the Navy under peculiar influ-
ences. which The Tribune has not hesitated TO
denounce Disaster. appalling in loss of life
and property and in the crippling of the fleet,
has been averted on several occasions only by
the vigilance and prompt action Of the officers
in charge The battle-shp Massachusetts,, for
example. was saved only by coOlness, haste and
skill from the treacherous grasp Of one Of these
so-called drydocks the latter Immediately there
after suffering partial collapse and adding an
other 10 the long list of like casualties which
the Navy has encountered in its few years OF
experience with these wooden structures.
The timber dock is really not a drydOck at
all. In fact II is unsafe TO make it dry 1t
Is watcrtight only about the abutments or en-
trance the remainder of the structure leaking
like a sieve and requiring-as at League ISL
and for instance-when a ship is locked a
pumping plant steadily in operation to remove
the volume Of water 1900 to LOO gallons
minutel which pours into the structure, the lat
ter acting. therefore, as only huge drain Tor
the surrounding soil. IN building such dock
the ground is excavated and wooden piling Is
driven for the bottom and sides. TO this piling
the timber lining is bolted. The structure Is
thus only step beyond the mud docks OF
China in that il has n wooden sheathing lt
is I'm principle in no way an advance upon the
craving docks of England of Queen ElZabeths
time. In our National policy as TO timber docks
we have taken n backward leap, TO be measured
only by centuries.
The chief danger 10 the wooden drydock does
not come from the waters Of the port 1t lies
in the hydrostatic pressure produced by tho
water in the soil surrounding the structure
which pressure tends 70 burst inward the SIDES
and 10 cause an upheaval OF the flooring. A
dock of masonry Is designed by its mere weight
10 resist these strains. With the fiimsy timber
dock. however. this is not possible, and inward
collapse is an ever-present danger. IL has Deeh
stated on competent authority that the sides OF
our naval docks Of wood open and close Ike a
bellows. one Of these structures being seven
inches wider at the top when ship is forced
into II than when empty. and without internal
lateral pressure. Furthermore the leakage
which IS essential 10 the safety of the timber
dock is ultimately a source OF danger, since
the water in passing through the seams TO the
dock. carries with It particles Of soil. Cavities
are thus formed exterior 10 the flooring and
sides. which may at any moment lead 10 rupture
and upheaval
These are the structures leaking, decayinG
and elastlc-which mistaken policy has In
ficted upon the Navy in place Of the noble and
changeless constructions which are found
abroad. Shall this policy be continued? In the
rebuilding Of its fleet the Nation has seen with
satisfaction huge sums expended that 1t might