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TJ^ A^inWCT ACROSS TTIiJ YQT.OCACY TtlY^T. ,1'^A':
FRED'S?. ICK, IIA.RYLAJ^'D
CFARI"RS Cr. C-RCSr
APniL £7, 10"-.:
Because this structur . "-. . part of reject
the rain v/orlc over shad ov/ed it ^•'^ -^f • +:'-^^-'^ -re no records preserved
regarding tl.e minute details of tiie construction. Eo^vever in
gathering the information presented the folloTTing where consulted
"History of Western Maryland", hy John Thomae ScLarf
(l34o-iC'. -■■ ) . "The History of Prederick County", ty Merriir.an.
loth of these works contc;.^!. ^i uetaileu ..^oou±^ of the section
re. :ted and much of the detailed history of the c;:i-Qil i::. li'^'-i^'
"T}ie Oreat Air.er:"cr:ir Canals", ty Archer Butler FulDert.
This v;or> contains the general hietory of the It o.
co 'ring a v ' account of that of the ' 1
Ohio C'.r-il. Professor T'ultert is conci-'ered an authority on the
history oi transportation, having taught history at I'arietta College,
Cl-.rhe University, Colorado Coll'?re, Tniversity of Chicago, Columhla
Univarsitj', an-'', othprs.
"An attOi.:i,t v/as made to oliain records fro:;; the present
ftffice of the corrvny, hut hecause of the lack of orga.nization none
of •;■ -^r- had h...^.. ^.reserved. However some info -<-'•'-■': 'or - - s gotten
fron; the reports of the CQ:':pany to its stockholders, which are
preserved in the Library of Congress.
Credit rrust also he given Sarmel lehowit-"; " --^.--.■: ...-. ^-^
this fraternity and a gr e in the class of 1926, for information
gotten froir; hi? thesis "The Chesapealce and Ohio Canal'.*
r n ^- .
THE AOU'aOUCT OYER Tl-'E J-OITOCACY RIVIE, KSAR
Tills aqueduct is a vortion of the syst'^rn of the Chesa-
X iTc.lce and Ohio Canal v;hich rune fron: C-eorgetoun in the District
of Columbia to CuKterland, Maryland "by •'j/ay of the Fotorcac Y-..lley.
Therefore a resuUiie of thc^^h.- ^ tory \7ill Toe given first.
There i^, v/here llilrty- second Street crosses it in the
District of Columbia, a monument v/hich tells that it v/as begun at
the Ceorcetov.-n end J'uly 4, 13.c3, and was completed to Cur.-terland
OctoLer 10, 1350. The Potomac Iniproverrent Coi'-.pany, cliartered in
1734 through the efforts of George Washington, opened n3,Tigation
betv/een tidev/ater and Cumberland by cutting short canal around
C-re:. t and little Palls and by bitting cha-nnels through the rocks
neca and Farpers Perry. The compo,ny did not pay, and in 1319
on .::^.pplying to the "Virginia Poard of Public TTorhs for releif th't
board directed its chief engineer, Thomas Yoore, to make a survey
to ::une the cost and feasibility of a canal fron t:' er
to the All&gany fountains. Moores report -ras ■ :-r 1-.£0 and hi?
■ of the cost vr.E '^1,11/, OCO. The Potor'-.^c Improveyrent Co.
■;:,3 bankrupt in 1321. Sentiment in Yir-inia, T'aryland, and Pennsyl-
vania favored t-e canal t:rough the Pctoi2-:.c Vo.ll'y and there was a
convention held on tj:e matter at Washington in 1323. Virginia and
?5aryland Incorporated the canal in 1824 and t.Vp United Stales ap-
proved tl-e incorporation. President Monroe signed the Canal rill
ITarch 3 1825 and a board of engineers xra.s appointed. They najned the
coT-r--- Hon The Chesapeake anek Ohio Canal Company. Tlie first spade
of dirt was turned by President Adams July 4, 1328 near Little
Falls. Construction continued frorc that time with many interrurtions.
The origin:.! cost estimate v.-as found to he much too lov; and many
difficul ■,7here encountered in raising the funds necessary
to coiQ.lete t^-j ^roject. Il eut. -finally completed at a cost of
over eleven million dollars. It v/as officially opened Octoher 10,1350,
The canal operated from the t:me of openln.o- until 1924
v/ith only various short periods of inteirup uion. The; ..iigineers,
in their alingment, forgot the fury of the Potomac River in the
s; ring of the year zo that at rrany points alcnr th ^ courr-e these
z'^.i'in^ f loo Is have caused much _• . The lasi ^ , iitT
of 1924 and the damage cai- .s sufficient to cause the suspension
of Oj. ons for a number of ronthe. The -^ ^--r.z vr ^
cc:.nal miu.le re;.,ay i'or traffic, but . oions vvhare never
Fror: the reports of tlie company one learns 'he
distance from Cumherjand to the Rod: Creel: Pasin is one hundred
and eighty five and five eight . : a total lift of five
hui . and eighty seven feet. The \vidth of th- canal varies from
fifty four to sixty fet with an average depth of six feet. There
are seventy four locl-cs with an average lift of eiglit fe^^t and the
v.^ter in the canal is drawn from sc-ven deonij, .i. _ Iso a total
of elev ACts and one tunnel v/hich is five eights of a mile
The u._„,«diict which is -ti-xe subject of this thesis is ihe
largest of the eleven on the main line of the canal. The only
larger one of the system, is one IGOO fs?t long which carries the
canal across the river froc; the Rod: Creek Easin to Hoeslyn froin
where it contlnuea to Alexandria. The ''dnocacy Aqueduct ''.Tas constr-
ucted iurin-_, the y-ars T'"'""^ and' 1831 "tut du--- to the absence of
records the exact dates could not he established. It crosses tlrxe
ITonocacy River at its junction v.dth the Potor.ac, and is thirty
eight miles v/est of "'ashington hy v/ay of the to^-p-th. It may he
reached hy taking the road from Hockvillo to Poole sville and con-
tinuing on until the river is reached.
It is of Kasonry construction and is four hundred and
thirty eight feet from one main abutment to the other, an:! the
ir.asonry of the v^dnged vralls and abutments extends ninety si:c feet
further. Tiiere are seven archs a.nd the lI_. intervening piers and
the abutr.ents rest on the solid rock of the river bed v/hich was
cleaned of sediment in order to make a firm foundation for the
structure. Tlie rock at tiiis point i;-.; a red sandstone .and fortunately
lies clo e to the surface in this district v/hich made a firm found-
ation easily obtainable. The . rchs of the structure (^^Ci hp^v^^ .--
af fifty four feet and a rise of nine feet. The piers h.-.ve c ti,ick-
nesE of ten fert and are about thirty five fe,?t long at th' base
giving plentiful support to the structure. The canal across th^
aqueduct is nineteen feet wide B.nd has a depth of six feet. There
is of course a to;,p:-th on either pide and tljat "lith the coping-
gives tiie --'-'-:;cture a Avidth of thirty :^e'-^t.
The entire structure is of rubble masonry v^ith the excep-
tion of the arch, the copine, the inside of the parapet, and the
water table, which are of cut stone. The stone used is tlie brown-
canal across the river from the Hocl: Creelc Easin to P.osslyn from
v;here it continue h to Al-xandria. The ITbnocacy Aqueduct \:-'^ constr-
ucted durinr- the y~:i^.Ta ISoO and' 1331 tut dur to the absence of
records the exact dates could not be established. It crosses the
ronocacy River at its junction v/ith the PotoF:ac, and is thirty
eight r.iles v/est of "'ashington by way of the tov.Tath. It may be
reached by talcing the road from Rochville to Poolesville and con-
tinuing on until the river is reached.
It is of masonry construction and is four hundred and
thirty eight feet from one main abutr.ent to the other, and the
m.asonry of the winged v.alls and abutments extends ninety sire feet
furtlier. There are seven archs and the six intervening piers and
th.v rebutments rest on the solid rock of the river bed r/hich vas
cleaned of sediment in oraer to ir.a]:e a firm foundation for the
structure. Tlie roclc at this point is a red sandstone and fortunately
lies clc e to the surface in this district v/hich made a firm: found-
ation ea.Eily obtainable. The ..rclis of the structure es-ch have a span
af fifty four feet and a rise of nine feet. The piers have a thick-
ness of ten feet and are about thirty five fe-'t long at th- base
giving plentiful sujxort to tlie structure. The canal across the
aqueduct is nineteen feet v;ide and has a depth of six feet. There
is of course a to'.path on either side and that v;lth the coping
gives trie structure a v/idth of thirty feet.
The entire structure is of rubble masonry v/ith tlie excep-
tion of the arch, the cox;ing, the inside of the parapet, and the
v;ater table, v/hich are of cut stone. The stone used is the brov/n-
stone which was very popular in masonry construction 'it that time.
It v. ..s quarried at Washington Junction v;?-lch is about ten miles
v;e£t of the site of the structure. The marvel of the construction
may he tetter realized v/iien one considers that all the rock h: 1
to he rei;-ov3i from the — usrriR hy han-i, hauled to the place of
cons true tic]-: Ly horse and v;a^-on, and cut and placed in the \Ta.ll
Toy hand. There v/as no machinery of any kind used in the construction,
Vox th? purpose of Vri= heater goTernis'ent of th^ corps
of engineers tho course of the canal -.vr?..^ divided into three districts
and these districtB suhdivid-d into Residencies, The First District
ei't.erd^d frOiT, Creorgetown to Point of P.ochs and v/3,s -ii^'vil'-i into
three L-esidencies. The Chief Engine rr at the time of the construction
of tliis acueduct was Judge Benjamin ".''right with whom were T. S.
Roberts and Erastus Fartineau as assistantsr. These three men ^ -->''■-
hno.vn officially as the Board of Sigineers and it was their d
to design all the structures connected with the canal an": tlierefore
tl'.if^ ar^ueduct - - ..1 . Ij. design. Tlie anueduct is in the Third Res-
idency and the Engineer in Charge of this Residency \7as 'FlrastuB
Ferd with Charles P. Pish as assistant. It -vcs t: ess menwho had
the direct supervision of the construction of the structure.
:-. ■".; li, heci.use of the excellent service re :.',
Ti.r. 1 _ ; i Chief Ingine'^r.
Alt!' ' '" - -hove : men ] -3 £;apc-vi;-^'jn oi con-
struction an inspection of tlie company ri'Cords she ^ ly
■rson '^: ctcr of S err-'. Upor.
hi- ^ onsil/ ili.it J for t*.'. c: otion of all , .'y
\7ork and therefore the construction of i ' i"
his superTision. ."^ fron the \70t': of Tni^; ectors today : .
evidently had a Laru joL oi it as L.c aiiiv-eixL. projects weve
t3J.h-let to private contractors and ivMCh of tlie lator was that
of slEj-Tes. The following is an ertract froiii th: ccrpuny specifica- ,
lion;:- ' ;i as, "Rulss Ada.. ' " . F--^- ' ^'----'or^ uf
The C .3 and Ohio Canal for the GoTermnent of the Corps of
En ineers", and outlines his duties:
"The Inspector of Stone a:.- „. onry will he
char£;:-^d with the inspection, discovery, and apj^roval
of all Quarries of stone Oj. ened for the supply of
materials to tlie canal, and all siasses of limestone
and tanlcs of sand, suited to the construction oi
any of its worh. The inspect -'on and approval or
rejection of all stone, lin-.e (both conmion and hydralic)
and sand, in every stage of their preparation for
use on the canal, according to the terms of tli"
contract made by the Presidert and Directors,
the President of the corfipany, the I'oard of Engineers,
and the Siigineer of the ^articular division on .vhich
any such stone, lime, or sand is to te enployed."
"He sh..,ll, after j:he stone has been conveyed
to the place where it ic to he used and prejared to
enter the wall, a second time inspect it "before it is
placed in the /.all. At this tirq^p, he shall designate
the facin.c stone of the lochs and aqueducts each by
an arj.ropriate mark and he shall, from time to time
inspect it and the ceiiient, both common and hydralic
as the stone is laid in the v;all."
Thus Ave see from the above extract th^^t although the
Board of Sngineers may be given credit for tlie excellent design
of the structure, the Tnsi-ector of Stone and Y/asonry deserves tlie
credit for the constraction and permanence of the structure.
Unfortunately his n.ame could not be found in the existing records.
The selection of the cer:ent was not left to the Insj^ector
of Stone and ITasonry however, but the most prominent engineers of
of/the tir;e were consulted in this selection. Tany intjuiiye.- v/ere
n.ade alDout the ceifient used UTjon other v/ork of a similar character
rruch of v.i.ich v/as in progress at this time in the United States.
After careful examination and chemical and practical te?^'^ "'■ ^
cement obtained near Shepardstov/n in '"aryland -vras adopted, and the
v/"isdoin of this selection is, greatly shoivn hy its condition at
Tl.e iTcisonry of this aqueduct seems to he of alriOst in-
' le character. In the spring of 1S77 a flood on tl s Potomac
River co ./reeked the canal th t it toolc two ^'u...j..; to repair it,
"cut V ' iUeduct T/.^s unharmed hy it. Again in 1897 and. 19d4 spring;
floods c ;.ch damage to the canal, "but a^ain this aqueduct
A comparison may he m:ade hetr;een this Ijct and the
one "hich carried the canal :?.cros£ Seneca Crr^:ol:, nhout ten miles
r '.VashinGLon. Tlie Seneca s.qusduct is in very "tad condition.
The stone has disinteg-rated in some places and m:uch o'f the mortar
has heen v;ea,thered from the joints causing much lea"lcan:e so tl':'. ""
at prssent ti.e aaueduct is alnost useless. Th^ I'onocc.cy aqueduct,
in comparison, is in just as good a condition as v/hen the canal
v/r s at its pjealc of op)eration.
The remarkable strength of the Tonocucy aqueduct v/as
sl-orn during the Ciril -Tar. The Confederates, in an effort to
cut this very important artery of corrmunicatlon and prevent suj;,i-lies
reaching the west, m.ade repeated a,ttempts to destroy' this aq^ieduct,
.Although they made repeated attem.p + s to destroy it they v.^ere foiled
"by the reF-arkaljle strength of the structure.
As ;7as scid "before tlie canal has not "been used since
19 -' and during the past ten year? ^ le^t £0 to ruin Eot2:at
_. ^ _ ont it is useless. Al&o ^'■.•j- the advent of thte railroad
it would no longer he ahle to haul at a jirofit. So today with
t-- e oth'^ir structures of the canal thi"- aqueduct stands as a
]:.onu::-t;i.t to a j;ast iiieanii of travel xa-at ne of "th^ ".. i.-i
larffeet of its tiir.e.