The Alexandria herald. [volume] (Alexandria [Va.]) 1811-1826, 1823-03-24


IS necessary. The ruins OF this kind OF
work are TO be seen some distance above
Cumberland. not however reaching TO
Savage river, and extend at greater or
less intervals TO where the general depth
OF water is considerably increased, be-
coming more and more rare, as the wa
ter is more abundant. They consist in
10" dams running across from shore to
shore, elevated about % inches or feet
from the bottom & made of rounded stone
picked Up out OF the bed Of the river, OF
the Size that man can conveniently handle
the greater part not larger than mans
head, and raised on a broad basi, of from
10 TO 20 feet III width. This transverse
low wall or dam is usually connected
with two walls about the same height,
but built on narrower basis of fom 6
to feet placed parallel to each o,he,, and
to the shores, at a distance of 20 feet from
each other, through which passage, by q
gap IN the transverse dam, 1t is intended
10 force the current of the river, ami 10
deepen the water by collecting II into this
artificial channel The number OF these
transverse walls connected as stated, with
20 feet sluices on the river, is very great
but 1t was not thought necessary TO count
them. Indeed in such slate of ruin
were the greater part of them found that
they were difficult to be distinguished
from the numerous fish dams found along
the whole course ofthe river A few, but
enough, OF them were in a sufficient state
OF preservation to be exarniI ed, and to
afford the means of ascertaining how far
hey were calculated to answer The ends
intended The commissioners are not
TO say what nigh: be the eff
eet OF this kind of walling oil other ii.
pers, but they are we'll assured that the
river Potomac cannot be useiuily confined
by such contrivancss; even if they we're
made in the best manner OF which .hat
kind OF yailing is susceptible. Ahs bot
Iam OF tins river which forms tbs drain
OF mountainous region of sucn vide
extent, is very unequal in its level, and
abounds IN shadows and basins, according
tn Its obduracY or softness, and TO The in-
creased o. diminished force oil he cur.
rent; sometimes weakened by expanding
IN widened plans, or in The 10. nlalIoI. Of
islands, sometimes increased by COntrac-
tUD between moub aims and rocky banks,
and above ali by Its tlo" ing SO iaLidly, IN
consequence oil the greatness II its tall
compared to itS length Inc resnlt .IoIn
situated in the bed OF such a river, Is ftin,aas
these walls cannot be made sufficiently
permanent, and IT they couiG. sc yc.y
many OF them would be required e at
ain even trihing depth that the benefit
would be infinitely too dear, Oh All auso-
ute waste OF money These walls from
heir nature cannot be ugh, but II hey
,ould be made sos and the whole oGdF
'f the water IN sucn q river, coulo DC
confined to channel Of 20 ieet, the We
ocity of the current rushing through
hese short channels with lulI room 10
spread after it has passed, would be in
in proportion TO its confinement.
And the whole volume of water IN the
river in the summer and dry seasons, esq
pecially above the south branch wouidnos
be sufficient to give the depth required
by boats of sufficient size TO be useful in
There the quantity OF wa
ter in this river IL much increased by the
larger tributaries in order 20 give lS
inches depth, and less would be OF no
use, il would be necessary TO continue
he parallel walls much furlhei than they
have ever yet been attempted, so az TO
give them length sufficient to reach o.
yer the whole extent of continued shall
lows, which were found in places to COW
CT three and four miles. The effect of
engthening the sluice walls would be In
some measure TO lessen the velocity and
Of course 10 increase the depth of the
current, but the evils are much too great
10 be usetully remedied by the small eff
iects whicb could be produced Ly these
means if 1t were practicable to give du-
Fsbility to walls so built and so placed
Walls Of this kind when drawn So long
and winding and bending as would bo
necessary TO follow the course of the cur
cir, you'd be obIec tionabie foI other rea.
SOUS independent of the increased cost
and increased liability to destruction -
Such as the extreme difficulty Of guiding
a BOAT with sufficient accuracy IN these
confined torrents so as to prevent
her striking and bilging against or over
The side walls III descending" and III as.
cending them, her progress would be
very much retarded by the increased
force OF the current consequent on its
confinement. Now Oh the suppositon Of
a large proportion of the distance being
a Il