REPORT
OF
THE ENGINEER
APPOINTED BY THE
COMMISSIONERS OF THE MAYOR AND CITY COUNCIL
09
BALTIMORE,
ÖN THif S'BBIBCT BA THE
MARYLAND CANAL.
BJ^TIMORE. '
PRINTED BY LUCAS It DEAV£B.
19, S. Calvert Street.
1837.
ENGINEER'S REPORT.
Baltimore, March, 1837.
To
James Carroll, ■
J. I. Cohen,
William Dickinson,
Commissioners of the Mayor and City
Council of Baltimore.
Gentlemen,—The appointment which' you were pleased to confer
upon me as "Engineer of the Mayor and City Council of Baltimore,
for the purpose of making the surreys, reports and estimates in rela¬
tion to the Maryland canal," having been placed in my hands on the
22d of September last, I forthwith proceeded to execute the trust
confided to me, with the view, agreeably to your wishes, of prepar¬
ing the subject for the action of the City Councils at their present
session.
It has been impossible, much as I desired it, to present the results
obtained at an earlier period.
To select the necessary competent assistants and instruments for
the organization of two field brigades—which unavoidably occasion¬
ed some delay, especially from the difficulty of procuring instruments
on a sudden requisition at a time when the demand for them was
unexampled ;* to make the surveys which we did ; to collate and
compare their results with a mass of information derived from' previ¬
ous surveys, embracing the whole scope of country from Westmin¬
ster to Georgetown ; to mature the whole subject, which for many
years has been a vexed one, so as to reach myself, a just conclusion,
and render it intelligible to others ; has, I find, been ample occupa¬
tion for myself and assistants for a period of less than six months.
By your instructions I am required to investigate this subject under
two different aspects ; the one with reference to "the ■practicability
of a canal with due supply of water exclusively within the territory
of Maryland the other with reference to the relative merits of each
route to the Potomac—or in other words, to ascertain the preferable
route, without restriction as to locality—-the route best calculated to,
secure to Baltimore the greatest portion of the western trade. '
• It was owing to the liberality of the Baltimore and Susquehanna Rail Road
Company that we were at last able to obtain, on a temporary loan, the principal
instruments required.
4
The question of a practicable route from the basin of Baltimore to
some point on the Chesapeake and Ohio Canal is fraught with mo¬
mentous consequences to this city. Its solution, under ordinary cir¬
cumstances, would impose upon me great professional responsibility.
Standing towards the city, as its engineer, somewhat in the attitude
of an agent whose opinion as to the preferable route may affect its
interest, now, and for all future time, I feel, superadded, a painful
sense of accountability, and therefore do not desire to, nor will it be
expected that I should, offer any excuse or apology for requiring all
the time which I deemed essential to do the subject, and especially
the interests of the city, justice, f proceed at once to the task.
In order that the subject may be fully understood by those not fa¬
miliar with the geographical features of the country between Balti¬
more and the Potomac, a brief description of its principal character¬
istics will be necessary.. Reference is requested to the general map
accompanying this report.
About 31 miles from Baltimore is an elevated belt of land, which,
sweeping roupd somewhat in a circle, from the Susquehanna river
to the Potomac, below: the mouth pf th® ;Monocacy, encompasses
Baltimore on the north, northwest and west.
This zone of land, called Parr's ridge, is distant about 125 miles
from the ocean on the east, and about 20 miles from the South moun¬
tain on the west. It has a well defined outline, and maintains, with
occasional depressions, a remarkably uniform elevation of about 850
feet above the ocean. It separates the waters of Codorus and Mono-
cacy on the north and northwest, from those flowing directly into the
bay of Baltimore and the Chesapeake. Like all mountains and elevated
lands this ridge discharges, in torrents, the waters which fall upon its
summit and sides, into the ravines and valleys of streams which rise
•at its base.
By reference to the map it will be seen that the Monocacy flows
into the Potomac west of Parr's ridge, and the Seneca immediately
east of it.
By a further inspection of the map, it will also appear, that, at
Damascus, a subordinate ridge deflects from Parr's ridge, and run¬
ning south eastwardly, with a pretty uniform elevation of 600 feet
above tide, separates into two otlier ridges at the head of Rock
Creek, which continue on in a south and south east direction with a
gradual descent, and terminate respectively at the heights of George¬
town and Vansville. The northern part of this subordinate ridge se¬
parates the waters of Seneca from those of the Patuxent.
It is apparent from the preceding description, that any route to
the Potomac, through the valley of Monocacy and its tributaries must
necessarily -cross Parr's ridge, while a route to the Potomac through
the valley of the Seneca will only traverse the subordinate ridge above
referred to.
5
Parr's ridge, and the subordinate one above described, interpose
a formidable barrier to any direct communication between Baltimore
and the Tallies of the Susquehanna and Potomac, at any point above
the mouth of those rivers.
However, notwithstanding its formidable character, à passage to
the Suequehanna on the north and the Potomac on the west, by
some mode of improvement calculated to secure a portion of the trade
of Pennsylvania and of the Potomac and Ohio vallies, has been for
years the object which has called forth the energies and. enterpiize of
Maryland and of her commercial emporium.
The favourable position of Baltimore equi-distant about 40 miles
from the tidal mouths of those great rivers and with easy access to
sea will enable her by artificial means to command the trade of both.
The elementary data with reference to heights and distances from
which conclusions have been drawn in this report, were obtained as
follows, viz ;
1st. From the surveys made under the Maryland Commissioners
in 1823, by Isaac Briggs.
2nd. For those made at various times for the Baltimore and Ohio
Rail Road, across Parr's Ridge.
3d. From the surveys made by Doctor William Howard in 1828,
between Baltimore and Georgetown, with reference to the Meiryland
Canal.
4th. For the surveys made under the direction of J. Knight, esqr.
for the location of the Branch Rail Road to Washington, for access
to which I am indebted to the politeness of that gentleman.
5th. From the recent surveys made under my own direction by Mr.
F. Harrison, in discharge of the duties imposed by your appoint¬
ment, and which were terminated on the 19th of December last.^
The surveys above enumerated intersect the country between Bal¬
timore and tire Potomac, and between Westminster and Vansville in
every direction, and furnish, in Connexion with minute personal ex¬
aminations made by myself on previous occasions, and especially
during the past fall, every useful fact connected with the subject of a
cross cut canal. '
The principal features of the country point out four prominent routes
from the basin of Bcdtimore, to the Potomac river ; all of which have
at different times, been advocated by general or local interests, and
their merits more or less investigated. They are as follows, viz :
1. The Westminster route,
2. The Linganore route, .
3. The Seneca route,
4. The route to Georgetown.
These routes have each their various modifications and ramifica¬
tions, which need not be pointed out, inasmuch as they do not affect
the comparitive merits of each other.
6
1st. Westminster route.
Distance, - 113 miles,
Lockage, ------ 850 feet.
Costs, - $
This route on leaving- Baltimore, would ascend the valley of the
Patapsco and its north branch to Westminster, and thence descend
by the vallies of Little Pipe Creek, and the Monocacy to the Po¬
tomac.
The great length of this route and its lockage would render it, as
a connexion between Baltimore and the Potomac, with a view to se¬
cure a portion of the western trade, unavailable ; even if it were pos¬
sible, within the limits of practicable expenditure, to construct a
canal on a scale commensurate with the public wants. This we do
not hesitate to pronounce impracticable.
It is not therefore, necessary to enter into needless details respect¬
ing it, or to institute a comparison between it and other routes faither
than has been done in table No. 3.
2nd. Linganore route.
Distance, ------ 81 miles.
Lockage, ------ 827 feet.
Cost, - - - - - - - f 8.810 DOG.
See maps and profiles of the summit level and adjacent sections,
No. 1 to 3, and map of basin line shewing the area drained.
The natural summit at Grime's tobacco house in a depression of
Parr's ridge, is 766.255 feet above mid tide at Baltimore.
A level of 238.255 feet below this point, has been assumed as the
lowest which the formation of the country will admit of, unless an
enormous sum were expended in the construction of a longer tunnel
than I have deemed most advisable ; a sum not warranted by even the
great object in view.
The length of this tunnel on the level assumed above, is 3 miles,
with a deep cut at each extremity of 50 feet.
As the natural flow of streams, the waters of which can be turned
into tliis summit does not yield enough to supply a canal of even the
most ordinary character and trade, with water ; the great deficiency
must be made up from reservoirs—the waters for which are to be ac¬
cumulated from the rains of the -wdnter and spring, from the greatest
area of country which can be commanded. We find by surveys made
that the area of country whose floods can be drained into the summit
level, is 26 square miles.
This includes a portion of the basin of Warner's Branch, which is
to be brought into the sumriiit by a deep cut of about 50 feet, through
the intervening ridge between it and Grime's Spring Branch.
7
The topography of the country adjacent to this summit, is repre¬
sented on the map of the Linganore summit.—
I shall now proceed to compute the whole quantity of water which
can be rendered available, as a supply for the summit level of this
canal. This maybe obtained from two sources. 1st. The natural flow
of streams above the summit level. 2d. The drainage of the area
of Country above the same summit.
I have, of course, rejected a mode of providing a supply of water
sometimes resorted to, but always attended with embarrassment and
partial failure, under the most favourable circumstances, viz : by ele¬
vating it by machinery from a lower level.
We shall first ascertain the quantity of water yielded by the natu¬
ral flow of streams, at points aboDe the summit level.
They are as follows, with the amount discharged by them as as¬
certained from repeated guaging.
Beaver Dams, 4.34 cubic feet per second.
Warners Branches, 3.75 do. do.
Grimes Spring Branch, 2.03 do. do.
Gilles Falls, above
Middle Run, ) 9.34 do. do.
Middle Run, 4.90 do. do.
Four Mile Run, .78 do. do.
Total, 25.14 cubic feet per second.
These guagings were made with extreme accuracy by dams at dif¬
ferent times in the month of November, when the streams were at
their lowest stage in that month. -
I am aware, that the guaging of streams affords more satisfactoiy
evidence of their minima quantities, when made in July, August and
September, usually the driest months.
The remarkable continuance of dry weather until late in Novem¬
ber last, was however, the subject of general observation, and justi¬
fies the impression that the quantity of water, as ascertained by guag¬
ing in November, did not greatly exceed the flowage in the driest
season"* However, where there is a question about the sufficiency
of water, no certain reliance ought to be placed on the quantities in-
* In corroboration of the above opinion, it is found by reference to the mete¬
orological observations made by Lewis Brantz, for the Maryland Academy of
Sciences, for 1836, that the quantity of rain which fell from July to November,
inclusive, was as follows:—July 1.32 inches—August 3.13 inches—September
1.28 inches—October 2.65—November 3.55 inches—Total 11.83 inches.
The mean quantity of rain which fell during the same months, from 1817 to
1824, by reference to the table of obsesvation of Lewis Bantz, is as follows :—
July 3.85 inches—August 4.30 inches—September 4.08 inches—October 2.98
inches—November 2.94 inches—Total 18.15 inches.
A comparison of these results will show, that last fall was an extremely dry
one. The difference during the five months beinp"6.32 inches.
8
(Heated by guagings, for but one season, unless under extremely fa¬
vourable circumstances for obtaining the minimum quantity.
These guagings, made in a very dry season, at all events
strongly denote the character of the streams; and taken in connec¬
tion with information derived from intelligent mill owners and
residents, as to the relative quantities discharged by them at
different seasons through a course of years, enables us to arnve,
with as much accuracy as is usually attainable in similar cases, at
their probable minimum supply in the driest season. We believe
this to be two-thirds of the quantity as ascertained by our guagings,
but to avoid, as far as we can, the liability to error, we shall assume
for the minimum quantity discharged by these streams at the driest
season, hut one-third of that as ascertained by our guaging in No¬
vember; or 8.38 cubic feet per second.
On the supposition that the streams discharge no more water at
any season of the year, than in the driest season, we shall have for
nine months, the period of canal navigation,
8.33x60x60x24x270=7.197.120 cubic yards,
27
which we are confident may be fully relied on, as the minimum an¬
nual supply from the natural flow of the streams, enumerated.
We will now compute the probable quantity of water which can
be annually stored into reservoirs above the summit level and made
available as a supply to it and the portions of canal contiguous.
The annual mean depth of rain and snow which fell at Lebanon,
Pa., from 1829 to 1836, was 40.46 inches.
The greatest depth which fell in any one year during that period,
being 44.78 inches, and the least depth 34.49 inches.
From observations made by Lewis Brantz, from 1817 to to 1824, in
the vicinity of Baltimore, it was ascertained that during the eight
years there fell a mean quantity of 39.89 inches.
The greatest depth which fell in any year being 48.55 inches, and
the least depth 29.20 inches.
From observations made at Germantown, Fa., by Reuben Haines,
from 1819 to 1827, it was ascertained there fell a mean depth of
38.10 inches. The greatest depth being 50.38 inches, and the least
30.73 inches.
9
Table No.'l.
Table of the Monthly depth, in inches, of rain ai Baltimore,
FROM MR. BRANTZ'S TABLES.
1817
1818
1819
1820
1821
1822
1823
1824
Mean.
January, . .
2.25
0.9
0.7
2.8
3.3
1.8
5.6
2.3
2.85
. February, .
2.8
2.
1.9
2.2
5.4
4.8
0.7
5.9
3.225
March, . . .
4.5
3.
4.55
3.3
1.7
1.3
7.1
4.3
3.71
April,....
1 5
2.1
2.7
1.1
2.1
2.1
1.8
4.7
2.20
May
2.6
6.45
4.1
4.4
5.1
1.5
2.1
2.95
3.65
June, ....
9.1
1.15
1.3
4.6
1.8
1.5
1.6
5.03
3.66
July, ....
3.5
4.1
2.2
2.2
7.5
4.35
3.6
3.37
3.85
August,. . .
10.4
2.0
4.3
8.0
0.3
0.8
4.1
4.5
4.3
September, .
3.3
3.2
3.0
1.5
10.7
2.25
5.8
2.94
4.45
October. . .
1.8
3.1
0.7
7.8
3.4
2.5
2.8
1.77
2.975
November, .
3.7
2.0
1.1
2.7
5.6
5 1
3.1
2.27
3.2
December, .
3.6
2.6
2.2
1.9
33
1.2
6.25
2.25
2.9
Amount,.
48.55
32.6
28.75
42.5
50.2
29.2
44.55
42.28
39.89
Table No. 2.
Tahle of the Monthly depth, in inches, of rain at Germantown,
BT REUBEN HAINES.
1819
1820
1821
1322
1823
1824
1825
1826
1827
Monthly
Mean.
January, . .
0.48
1.70
3.38
3.67
1.84
1.48
2.72
2.18
February, .
2..55
4.82
2.90
3.86
3.94
4.54
2.50
3.57
3.58
March, . . .
5.01
0.57
2.20
6.87
2.63
5.40
3.54
1.42
3.07
April
3.05
2.16
1.77
4.54^
0.75
3.02
3.06
2.62
May
6.36
5.92
2.17
1 60
1.59
2.57
0.22
2.58
2.87
June, ....
1.88
2.60
1.44
0.87
6.09
3.94
5.98
2.98
3.22
July
0.74
6.50
1.84
3.89
6.12
8.80
1.68
5.87
2.90
4.25
Augnst,. . .
3.86
3.64
0.41
1.33
4.68
6.39
4.06
4.30
6.56
3.48
September,.
2.44
1.95
5.74
5.45
3.46
6.60
2.23
2.82
1.18
3.27
October, . .
0.94
8.94
3.24
1.24
2.02
1.53
1.70
5.38
6.57
3.50
November, .
1.00
3.12
4.65
5.00
2.47
2.49
1.05
2.05
5.30
3.01
December, .
1.46
3.25
2.84
1.25
7.37
2.11
3.60
1.47
4.09
3.05
Amount, .
10.44
43.20
36.06
30.73
44.47
50.38
33.36
38.63
42.93
38.10
2
]Ö'
The average annual depth of rain deduced from these three series
of observations, extending through a term of nearly 18 years, appears
to be 39.48 inches.
The average of the least depth of rain which fell in that period,
derived from the same observations, is 31.47 inches.
The observations we have referred to, were made with great accu¬
racy, and may be fully relied on.
Those taken at Lebanon show a greater fall of rain by several
inches than either of the others. This is very satisfactorily account¬
ed for by the greater elevation on which the rain fell ; Lebanon being
about 7 or 800 feet above tide, which would give it, together with
exposure, an average temperature of at least 3® of Farenheit colder
than either of the other localities.
It is well known that greater quantities of rain fell on elevated
than on low grounds in consequence of the difference of temperature,
exposure, &c.; hence for our purpose, we deem the result of the ob¬
servations at Lebanon most appropriate ; especially as the local
causes at Lebanon and Parr's Ridge—from almost exact similarity
of situation, elevation and exposure—must operate to produce the
same effects. They are each 130 miles from the sea coast ; their
elevation above the ocean is nearly the same, and they are each about
20 miles distant from the most eastern ridge of the Appalachian
chain—the South or Blue mountain.
Parr's Ridge, from its height, witliout any elevated ground inter¬
posed between it and the ocean, and having none west of it for 20
miles, has a position remarkably favorable for the accumulation of
clouds and moisture. Hence the proverbially copious and constant
springs issuing from its sides.
These considerations, in our opinion, would fully justify the adop¬
tion of the result obtained at Lebanon, and the use in our calcula¬
tions, of the average quantity of rain which fell there for a period of
seven years, viz:—40.46 inches.
However, it will be safer to take an average of the mean quaiitity
of rain which fell at these places.
Lebanon, 40.46 inches.
Germantown, 38.10 "
Baltimore, 39.89 "
118.45 -Í- 3 = 39.48 inches.
But to diminish still further the possibility of error in the computa¬
tion, we will take an average of the least quantity of rain which fell
at each place—
Lebanon, 34.49 inches.
Germantown, 30.73 "
Baltimore, 29.20 "
94.42 -4-3=31.47 inches.
11
"That is, we aie satisfied that the least quantity of rhin which falls an¬
nually over the whole aiea of 26 square miles on Parr's ridge, amounts
to 311 inches.
The next step is to determine what amount of this annual fall can
be accumulated into reservoirs ; that is, what quantity will remain
after evaporation, filtration, &c. have taken place.
Since there are no means of ascertaining the amount of evaporation
and filtration with absolute certainty^ the opinions and observations
of those whose occupations lead them to observe closely the results
obtained in other cases, must he brought in aid of our observation
and reasoning, with reference to the one before us. >
The following results obtained from the well known experiments
of Dalton & Hoyle in England, show the proportion of evaporation
from the ground, to that of rain., to he as 2 to 3. •
Inch of
rain.
Inch ef-evapo¬
ration from the
ground.
Inch of evapo-
tation from
water.
January, '
2.46
1.01
1.50
F ebruary,
1.80
53
, 2
March,
90
62
3.50
April,
1.72
1.49
4.50
May,
4.18
2.69
4.96
June,
2.48
2.18
6.49
July,
4.15
4.06
5.63
August,
3.55
3.38
6.06
September,
3.28
2.95
8.90
October,
2.90
2.67
2.35
November,
2.93
2.08
2.04
December,
3.20
1.48
1.50
■
33.55
25.14
44.43
The foregoing experiments were made on a level surface, for the
purpose of ascertaining what proportion of all the rain which fell was
evaporated, and what portion was absorbed by the earth, to the
depth of 3 feet beneath the surface.
It is obvious that the result would have been widely different, had
the rain fallen upon a surface sufficiently inclined to admit of its
flowing rapidly off.
Without enumerating the opinions of authors and engineers on the
subject of the ratio of evaporation, it may be observed, that opinions
on this subject are usually given with reference to some particular
case, under some circumstances which have a control ov.er it ; such
as the nature of the soil on which rain falls; the structure of the sub¬
strata : the gentleness or abruptness of the slopes of the hill sides ;
the distance water has to flow ere it can reach the reservoir; the ex-
12
istence or absence of forests ; heat of climate ; prevailing winds ; ele¬
vation, &c. &c.
Suffice it to say, these opinions vary in ascribing the loss by eva¬
poration and filtration from to | of the annual fall of rain. Or in
other words, that in some situations | of the annual fall of rain can
be storeci into reservoirs ; in others but —not including the evapo¬
ration from the surface of the reservoir when filled.
From the practical knowledge and observation of William Cubitt,
Esq., one of the most eminent civil engineers of England, espe¬
cially for the construction of canals—he expresses the opinion,
that the available quantity of water which can be stored in reservoirs
in England, is about one half the annual fall of rain.
It is well known that by far the larger portion of surface land in
England is clear of forest and under cultivation, and that the face of
the country is comparatively flat; circumstances very well calculated
to evaporate and absorb a large portion of the rain which falls, before
it can find its way into reservoirs.
Viewing the district of country on each side of Parr's ridge, the
circumstances ate widely different. The surface is elevated and
covered with forrests ; the soil unbroken by cultivation and hence
favourable for shedding off" wmter ; the slope of the hills short and
abrupt—a combination of circumstances admirably calculated to dis¬
charge rajiidly the water falling on the surface, into reservoirs, before
evaporation and absorption can take place to any great extent.
In consideration of these facts and deductions I do not hesitate to
express the opinion, that in this particular district two thirds of the
annual fall of rain can be collected into resevoirs. But on a more unfa¬
vourable supposition, desiring always to be safe, we will take but one
half of the annual fall of rain, and that not from the average of a term
of years, but from the driest year known during a period of near
eighteen years, as ascertained at Lebanon, Germantown and Balti¬
more, viz : 15f inches, for the annual proportion of rain which can be
accumulated in reservoirs.
As part of this will be lost by evaporation and filtration, afler it has
been stored in the reservoir and during its use for the canal, it is ne¬
cessary to assertain how much these two items will amount to, in or¬
der to show what will be left as the available snpply for the canal.
We conclude from numerous data that during the six months from
October to March, the fall of rain on the surface of the reservoir will
make good the loss by evaporation and filtration. The tables con¬
structed from observations of Dalton and Hoyle conclusively show
this. The same tables show that the evaporation during the six sum¬
mer months, from the surface of water, exceeded the rain which fell
on it, by 12.18 inches, or l-15th of an inch per day. William Cu¬
bitt states it at 1-lOth of an inch per day, or 18 inches for six months.
As our summer climate is more arid in this country than in Eng¬
land and evaporation consequently greater, we will suppose it to be
13
double Mr. Cubitt's statement, or 36 inches for six months, lost off the
surface of the reservoirs, by evaporation ; although their depth exceed¬
ing 30 feet, (which would prevent the temperature of the strata at the
surface from becoming greatly heated by the sun) and the elevation of
the district above the sea, might justify us in fixing the loss at a
lower rate.
For loss by filtration and soakage from the reservoirs, we may add
24 inches, in consideration of the very favourable positions for dams,
which will make reservoirs of the valleys of large streams, already sa¬
turated with water, and consequently well adapted to retain all that is
accumulated in them. On this point Mr. Cubitt states, "the amount
of soakage in many canal levels known to me, is certainly far less
than the amount of evaporation, and both together would not exceed
an inch per week"
Howev-er, in accordance with the rule we have prescribed to our¬
selves, viz : to err on the safe side, we put down the loss by filtration
and soakage the same as the evaporation, viz : 3 feet, making the loss
from the surface of the reservoirs by evaporation, filtration and soak¬
age, for the six summer months, 6 feet, or, assuming the depth of re¬
servoirs, which we may safely do, at 30 feet, the loss from all these
causes together is l-5th of the whole amount of water, which can be
accumulated in them.
We now have the data for computing the annual available sup'ply
of water which can be commanded from drainage and the natural
flow of streams : as follows.
1st. BY DRAINAGE.
One half of the annual rains on 26 square miles gives
1760xl760x.4376x26 = 35.243.253 Cubic yards.
Deduct, loss by evaporation and soakage
from surface of reservoirs, at one fifth, 7.048.650
Total amount available from reservoirs 28.194.603 Cubic yards.
Add available flow of streams as before
ascertained, - - - - 7.197.120
Total available quantity - - 35.391.723 Cubic yards.
We thus find the total available quantity of water from all sources
to supply the summit of any canal by the Linganore route to be
35.391.723 cubic yards annually.
We wiU now proceed to ascertain the quantity of water which a
canal will require, of the dimensions appropriate to the trade which
the Maryland Canal is expected to transfer to Baltimore.
First, as to the dimensions of a canal, which will probably be able,
to meet the public wants in the event of an active trade when the
Chesapeake and Ohio Canal shall have been finished to Cumberland.
14
We will not pause here to discuss the relative merits of large and small
canals in connexion with the thade of the valley of the Ohio
and the great west—-That question was ably discussed and deci¬
ded by the Board ol' Engineers for internal improvement of the general
government in their able report on the Chesapeake and Ohio Canal in
1826—Suffice it to say, that large canals are pieferable in almost all
situations, though from motives of economy small ones are some¬
times prelerred. With a view to but even a small part of the trade of
the west, they are absolutely essential.
The dimensions of the Chesapeake and Ohio Canal above Har¬
per's Ferry, are as follows, viz : 50 feet on water line, 32 feet at bot¬
tom, and 6 feet deep with single locks—It would seem to be unne¬
cessary to assume any greater capacity for the cross cut canal to Bal¬
timore than that possessed by the Chesapeake and Ohio Canal above
Harper's Ferry; since if no portion of the western products or coal
goes to Georgetown, the trade on the former cannot greatly exceed
that on the latter.
But as public works, made during the rapid expansion of internal
commerce and agricultural improvements of our country; when new
projects and schemes of vast extent and importance, the mere crea¬
tions of fancy to-day, may become splendid realities to-morrow—
should not only be adequate to the existing wants of the communi¬
ty, but capable of meeting future requisitions and accessions of com¬
merce; we shall assign to this canal larger dimensions than those of
the Chesapeake and Ohio Canal above Harper's Ferry. On the sup¬
position too, that much detention will ensue in consequence of the
great number of locks, this inconvenience on the cross cut canal
should in part be remedied by increasing its section, and the con¬
struction of double locks.
In accordance with these views we shall fix the width at the sur¬
face at 60 feet, at bottom 32 feet, with a depth of 6 feet, and double
locks of 100 by 15 feet, and 5 feet lift.
These data being established, I proceed to complete the supply
of water needed for the summit level of the canal and the contiguous
portions, amounting to a length of 12 miles. Add for feeders from
reservoirs, 3 miles, and there are 15 miles to be supplied by the water
at command.
I shall divide the expense of water caused by the canal into two
parts, viz : Lockage and waste. The latter including loss by evapo¬
ration, soakage, filtration, &c.
1st. Lockage—On the plan of double locks, one boat each way will
require, if the ascending boats, alternate with the descending ones,
but one lock full of water each, to pass them over the summit; which,
on the supposition of an active trade would cause but little delay, as
there would always be ascending boats ready to take the place of
those descending ; and as there will be as many boats passing in
one direction as the other, there would be but two locks full drawn
15
from the summit at each cross passage. But on the most unfavora¬
ble supposition there can be but three locksfull drawn oif for each
cross passage, as follows : "A boat going east arrives at the eastern
end of the summit, double locks, say both empty—one lock is filled,
drawn off for its transit, but in drawing off this lock full one half
of it is discharged into the twin lock by a communication between
them a boat immediately follows in the same direction, and there
is one going westward waiting its turn to be lifted into the summit
level. The ascending boat enters the empty lock, which being filled,
draws off a lockfull—-the ascending boat waits till the lock which is
half full, is filled, which draws off half a lockfull, or Ij locks full for
the cross passage of the two last boats—Or, to explain it more brief¬
ly, one lock at each end of the summit level is always kept half full of
water, by a communication between the locks, which of course saves
half a lock full on each cross passage, and reduces the expenditure
of water to 1 è locks full at each end, or 3 locks full in passing two
boats on the summit.
The liberal supposition will now be made that the activity of the
trade requires the transit of 125 boats per day, each way, for a period
of nine full months, or 270 days, which is found to be the longest
season of canal navigation—Then these 125 boats, each way, will
consume per day,
Lockage, 15x100^x5x125x3 = 104,166.66 cubic yards.
Waste 15x75x60x24 _ 60.000.00
27 164.166.66 cubic yards per day.
Total required for the use of
the canal, for 270 days, 44,324,998.20 cubic yards.
The waste water which we have computed above, consists of eva¬
poration, soakage, filtration, leakage of lock gates, &c., from the
surface sides and bottom of the canal, for the whole distance of 15
miles, for which I have allowed 75 cubic feet per mile per minute.
General Bernard, in the able report on the Chesapeake and Ohio
Canal, 1826, estimates this waste for the summit level and adjoin¬
ing portions at 62 feet per mile per minute.
I- have the authority on Benjamin Wright, Esq., for saying that
50 cubic feet per mile per minute, on a, well constructed canal, is am¬
ple allowance.
Doctor Wüliam Howard, fiom minute personal inquiries on the
Erie canal, fixed evaporation, filtration, and lockage, after the banks-
had become consolidated, at 90 cubic feet per mile per minute.
In 1824, judge Bates, who had charge of a portion of the Erie-
canal, took great pains to ascertain the loss by evaporation, filtratioru
16
and soakage, the first year the water was let into his portion of the
canal. He found it to he 100 feet per mile per minute.
There had been no puddling and the soil was porous ; and as is
well known in all new canals, the filtration and absorption must have
been far more than usual.
The waste of water on a canal has been put down by engineers
at from 50 to 75 cubic feet per mile per minute. I have never known
greater allowance made on a well constructed canal than 75 feet.
Under the favourable circumstances found at Parr's ridge, I think
this ample allowance, and have accordingly estimated the waste as
before.
By recapitulation it is found that the whole available annual sup¬
ply of water which can be collected on the summit of the Linganore
route, from a drainage of 26 square miles, and from the natural flow
of the streams amounts to 35,391,723.20.
That there is required for the due supply of a canal by this route,
with an active trade for but 9 months of the year, 44,324,998.20,
leaving a deficiency of 8,933,275.20 cubic yards.
I therefore reach the conclusion that a canal by the Linganore
route, of the requisite dimensions and capacity, with due supply of
water to support the trade which may be carried upon it at the pe¬
riod of its completion, is impracticable.
This route leaving Baltimore pursues the valley of the Patapsco to
Elk Ridge Landing ; thence ascends the vallies of Deep and Licking
runs to Merrill's ridge, thence across the ridge, and down Chandler's
branch to the North branch of Patuxent; thence crosses the tongue of
intervening land at a depression, near a school house, and reaches
the main Patuxent ; thence ascends the same to Etchison's mills ;
thence crossing the summit descends the Seneca to the Potomac.
The subject under consideration being the practicability of carry¬
ing a canal over this summit, with due supply of water, our investi¬
gations will be confined to this point.
The principal surveys made last fall were in this district. Four
separate lines were traced across the summit within a space of four
miles, with a view to develope every fact, which might have an in¬
fluence in solving the question of a practicable canal communication
over it. Here we will observe, that surveys over this summit were
never before made.
These lines and the topography in their vicinity are accurately laid
down on the map of this summit, to which reference is requested, as
Seneca route.
Length,
Lockage,
Cost,
76 miles.
761 feet.
$6,324,300.
1?
also to the maps and profiles from the Washington road to the mouth of
Seneca, Nos. 1 to 9. I -would here repeat the remark that the
ridge which forms this summit, is not the Parr's ridge—but a spur
from it diverging at Damascus, in a south-east direction, and divid¬
ing the waters of the Patuxent on the east from those of Seneca on
the west.
It is similar in character and appearance to Parr's ridge, though
much less elevated.
Patuxent river rises near Parr's spring, flows south-easterly, and
after a course of eight miles receives Cabin branch—a tributary from
the north, seven and a half miles long. Four miles lower down it
receives the Cattail branch, nine miles long, also from the north.
Six miles further Hawling's river enters, twelve miles in length ; a
stream whose character was compararively little known until the re¬
cent surveys. These are the main branches of the Patuxent in this
district, and are remarkable for their constancy.
By an inspection of the map of this summit it will be perceived
that about two miles above the mouth of Cabin branch, the Patuxent
approaches within a short distance of the Dividing ridge, between it
and Seneca. In fact the river may be said to run against the ridge
at this point, cutting off, as it were, a portion of its base on the
eastern side, and reducing it to less than one mile. Opposite to this
point on the west side of the ridge, one of the chief branches of Se¬
neca takes its rise, and after a course of 3 miles, receives a large branch,
four miles long heading at Damascus—one and a fourth miles further
Magruder's branch enters—four miles long; one mile further, Wild
Cat branch empties in—a stream of about the same length as the
preceding; descending still further. Daws' branch, four miles long,
comes in from the east; four miles further down. Whetstone branch,
four miles long, unites with Seneca at Middle brook. These are the
main branches of Seneca, and are fed by constant and copious springs.
A cursory view of the ridge in the vicinity of Henry Griffith's
seemed to justify favorable expectations, as to the facility of passing
the canal through it. In consequence a careful line was traced across
it, and its position, elevation, &c., with respect to the adjacent county
carefully ascertained.
It was found to be both narrower and lower than at any point for
several miles north-west or south-east of it.
The height of the ridge at a depression a'oout one mile north of
H. Griffith's, is 578.83 feet above mean tide, and 122 feet above the
Patuxent at Etchison's mill.
A tunnel of 690 yards length, at this point, with a deep cut of 50
at each extremity, will reduce this summit to an elevation of 495 feet
above tide and 36 feet above the Patuxent at Etchison's Mill. This
elevation has accordingly been assumed as the summit level of a canal
by the route now under consideration. . , . ... .
Ï8
A height of 36 feet above Pátuxent was chosen with reference to a
remarkably narrow pass on this stream about miles above, near the
Annapolis Rocks. The level of the water in the stream at this pass,
is the same as that of the summit proposed for the canal. Conse¬
quently, a slight dam and feeder would divert the waters of Patuxent
into the Seneca, were this tunnel constructed. A cut of 40 feet near
the Annapolis Roeks, will also divert the waters of Cabin Branch,
into the Patuxent.
As the natural flow of streams, which can be brought into the sum¬
mit, is not sufficient to supply the wants of a canal, resort must be
had to reservoirs, as on the Linganore route.
It is upon the natural flow of Patuxent, Cabin Branch, heads of
Hawling's River and branches of Seneca, and the drainag.e of the
basins of these streams, that we propose to rely for water to supply
the summit level of the canal and adjoining portions.*
For the latter purpose, a part of the annual fall of rain on the area
of those basins must be collected into reservoirs, during the winter
and spring. The vallies of Patuxent, Cabin Branch and Seneca, are
admirably adapted to the formation of artificial lakes, by dams,
erected at no extraordinary cost, across them ; remarkably favourable
sites for whicb, are numerous.
The rain falling in these basins is discharged rapidly from steep
side hills, as from so many roofs, into the vallies below.
It is this favourable character of the country which will enable us
to accumulate a large portion of the. annual rains, which, if they fell
on a more extended and level surface, would, ere they could reach the
reservoirs, be exposed to evaporation and leakage in so great a degree,
as to deprive us of a large portion of the winter and spring floods.
We proceed at once, to compute the quantity of water which may
be relied on to supply the summit level and adjoining portions of the
canal, extending from the mouth of the Cattail on the Patuxent tO'
Wild Cat on the Seneca—a distance of 12 miles.
We reject, as we did on the Linganore route, all methods of sup¬
plying the canal with water, by elevating it from a lower to a higher
level by machinery. . ,
The area which can be commanded for the purpose of collecting
water into reservoirs to supply the summit level and adjoining portions,
amounts to 46 square miles, without including the inferior areas
amounting to 12 squme miles, which can also, without extraordinary
expense, be made to contribute their portions of annual drainage.
* In ascending the Patuxent, the discharge from Cattail, Hawling's River,
and the Patuxent, not estimating the redundant water from the summit—willv
without a reservoir on Cattail—certainly with it, supply the lower portions of the
canal with water ; while that portion of canal in the lower Seneca valley will in
like manner, be supplied with water from Wild Cat, Daw's Branch, Magru-
der's Branch, Whetstone Branch and Seneca.
The character'of the district adjacent to this summit, with regard
to flo wage of streams, drainage, &c., being entirely similar to that on
the Linganore route, it is not necessary to indulge in any repetition
respecting them.
The same data, deductions, and reasoning will be used on this,
which were used on that route, varied only so far as to render their
application just and proper.
Assuming as before, that one half the annual fall of rain can be
stored into reservoirs, and that 4-5ths of this can be made available
as a supply for the use of the canal. We have the following result
from an area of 46 square mile§. ■
Cubic Yards.
1760xl760x46x.4376, ' 63.253.448.96
Loss by evaporation, &c., l-5th, - 12.470.689.79
Available annual supply from reservoirs, 49.882.759.17
The streams whose natural flow can be rendered available to feed
the summit level are as follows—with the quantity of water discharg¬
ed by them per second, by measurements made in November.
Hawling's River,
Patuxent,
Cabin Branch,
Darby's Br. of Seneca,
Seneca,
Adam's Run,
Daw's "
Riggs Run,
White's Branch,
Lemmon's Branch,
3 small branches,
Total,
As before remarked on the Linganore route, we might in conse¬
quence of the dryness of the last fall, take % of the above as the av¬
erage discharge in August, for a term of years. We will however for
reasons given before, assume but i of the quantity as above, or,
11.27 cubic feet per second, the minimum discharge at the driest
season, which gives for the 270 days of canal navigation, a yield of
11.27x60x60X24x270 = 9.737.280 Cubic yards
■ 27 '
Add quantity supplied by reservoirs 49.882.759.17
Total 59.620.039.17
Thus we have for the total available supply, the foregoing result.
The next step is to ascertain the wants of a canal such as we
contemplated on the Linganore route, with the same amount of, trade
4.98
Cubic
Feet
7.65
(C
5.01
CC
u
6.03
u
a
3.83
tc
(C
1.56
ÍC
u
.48
u
a
1.99
ii
u
1.17
u
u
.57
«
u
1.53
ii
u
«
u
33.80 cubic feet per second.
20
as there assumed, viz. 125 boats per day in each direction for 270
days.
1st Lockage 15x100x5x125x3 = 104.166.66 Cubic yards.
27 ,
2d Waste on 12 miles of canal
and 11 " of feeder
23 Miles.
23x75x60x24 = 92.000.00
27 Total 196.166.66
or, for 270 days, 52.964.998.20 cubic yards.
' Recapitulated.
Total supply 59.620.039.17 cubic yards.
Wants of canal '52.964.998.20
Surplus 6.655.040.97 cubic yards.
Leaving a surplus of 6,655.040.97 cubic yards annually for con¬
tingences of all kinds.
From the foregoing facts and deduction we are forced to the con¬
clusion, that a canal by this route, with due supply of water, for an
active trade is practicable—and however much we may regret a va¬
riation of opinion with predecessors, whose character entitles them
to confidence, but who have not of course reasoned from the same
data as ourselves—else would they have ariived at the same conclu¬
sion—we are compelled to announce the practicability of a canal by
the Seneca route, especially as an additional area of 12 square miles
can be drained into the canal adjoining the summit which will yield
18.972.800 cubic yards, increasing the surplus to 25.549.374.30
cubic yards annually.
Having expressed the above opinion, candour compels us to say
at the same time, that the supply of water for a canal, obtained from
reservoirs^ has been usually attended with partial disappointment,
either from hidden causes or defective calculation, and that every
sound engineer would seek, in preference, a supply from other sources
if such were within his reach. However, numerous canals are in opera¬
tion in this country and Europe, whose chief supplies are from reser¬
voirs.
An interesting fact relating to the demand for water in the driest season is
found in the report of the canal commissioners of Pa. for 1836, viz. that the
months of most active trade are June and October, when water is comparitively
abundant. In 1836 the trade on the Pennsylvania canals in August, was to that
of either June or October in the diminished ratio of 46 to 72 or 37 1-2 per cent
less, and that the trade of July and September was to that of June and October
in the ratio of 122 to 144, or 15 per cent less.
These facts would show that the demand for water during the months of July,
August and September, but especially in August, will be much less than we
have allotted in the preceding estimates. ■
•21
4. Route to Georgetown, D. C.
Length, 44j miles.
Lockage, - - - - - - - 262 feet.
Cost, - - - - - ^3,530,000
For the route of the canal to the District of Columbia we might
for our comparisons, adopt that preferred by Dr. William Howard,
eminently qualified as he was on the subject, on experimental sur¬
veys made in 1825, under his directions.
There are, however, some changes from this route which we deem
advisable, and which were in fact suggested, and would doubtless
have been selected by him, on further maturing this pletns and on
making a final location.
The principal change consists in the selection of the most south¬
ern line, spoken of by Dr. Howard, from the point where his route
crosses Merrill's ridge to Bladensburg. By this route, deep cuts
similar to those he projected through Middle ridge and Snowden's
ridge—the first between two Patuxents, with a cut in the deepest
place of 74 feet and If miles long—the second, between Big Patux-
ent and the eastern branch of the Potomac 72 feet greatest depth,
and 2i miles long ; may be substituted by others of very ordinary
magnitude through the same ridges, but at much lower depressions.
The propriety of this change is fully confirmed by facts developed
oil the surveys made under the direction of J. Knight, Esqr., for the
location of the rail road to Washington.
From these surveys it appears that the ridge or tongue of land be¬
tween the two Patuxents on the most southern route, suggested by
Dr. Howard, is at a depression near a school house, but 135 feet
above mean tide—and that a depression in Snowden's ridge on the
farm of Zelic Duvall, is 155 feet above mid tide. The elevation
of land and nature of the soil, &c. at these two points, exhibits the
most favorable character both for slight cuttings and easy excavation.
The height of the summit level assumed by Dr. Howard, is 146 feet
above tide—This level if carried through the route we have spoken
of, would be 21 feet above the depression in Middle ridge—and but
9 feet below that at Zelic DuvaU's.
These facts are of extreme interest in connexion with the propos¬
ed canal, and show that not only a lower level through Middle and
Snowden's ridges than that referred to by Dr. Howard, will be ex¬
pedient, that the height of the summit and consequently lockage,
may possibly be diminished vrith advantage, but also that the cost of
the formidable cuts through Middle and Snowden's ridges, may be
so reduced as to require nothing more than an ordinary expenditure
of money.*
•It is confidently believed that such a level for the canal can be assumed, as
will avoid the necessity of any injury to the extensive Savage Cotton Factory
on the north branch of the Patuxent.
These facts also present the subject in so new and favorable a
light, that it is scarcely necessary for me to suggest the great pro¬
priety of making further surveys during the ensuing summer, with
reference to this special object.
The estimate of cost which has been prefixed to this chapter, has
been made on the assumption that a canal on the most liberal scale,
with double locks, to meet any future emergencies of a crowded trade,
will be necessary between Baltimore and the District.
We have carefully reviewed Doctor Howard's estimates, made
in detail, with all the advantage of his experience, while with
the Board of Internal Improvement of the general government
for several years ; during which time he assisted to frame the
estimates for the Chesapeake and Ohio Canal, the accuracy of
which subsequent experience has so fully verified—and have ar¬
rived at the conclusion, viz : That although the wages of labor,
&c., are greater now than at the time these estimates were made,
the cost of the canal, in consequence of avoiding the deep cuts
alluded to, and including the necessary walling, not estimated by
Dr. Howard, will very little exceed the entire cost as estimated
by him', viz, $2,980,815,40—We, have, however, supposed it may
reach $3,530,000.
Doctor Howard investigated the resources for water on this route
with great care. Numerous guagings of streams were made, and
repeated after an unexampled drought in the autumn of 1828, when,
as he remarks, "the inhabitants observed that the waters were then
lower than at any previous time within their recollection."
He ascertained that at this season of drought there could be com¬
manded to supply the summit level 40.19 cubic feet per second;
which he deemed amply sufficient to supply it with water, with¬
out the aid of reservoirs. Should a resort to these be unexpect¬
edly necessary, there can be accumulated by dams, at remarkably
favourable points across the Patuxent, water, to the most redundant
excess.
The portion of canal next to Baltimore wiU be amply supplied
from the Patapsco, and that between Georgetown and Bladensburg
will recèive abundant supplies from the Potomac.
There can be no question, therefore, without going into details,
that an ample supply of water for the whole canal on the most libe¬
ral scale, and with double locks, can be obtained at a moderate
expense.
23
The following table will exhibit a comparison between the four routes.
Table No. III.
Miles
lengtli.
Lock¬
age.
costs.
Dolls. Ct3.
Is
2
3
4
5
6
Westminster route,
Linganore route,
Seneca route,
Georgetown route,
Mouth of Seneca to Georgetown
by Ohio and Chesapeake canal.
Mouth of Seneca to Baltimore,
via. Georgetown, ........
113
81
76
44f
23
850
827
761
262
205
431
■
8.810.000
6.324.300
3.530.000.00
Of the preferable Route to the Potomac,
It now becomes necessary to determine which of the two practi¬
cable routes in the preceding table is best calculated to secure to
Baltimore a portion of the western and coal trade.
This enquiry has on various occasions elicited the feelings of the
citizens of Baltimore. It is now invested with extraordinary inte>-
rest, as the time approaches for the completion of the Chesapeake
and Ohio Canal to Cumberland, and calls for some decided and
vigorous movement on the part of the city to secure to her the advan¬
tages she possesses from locality, and the benefits of the coal trade,
which she may well claim for the uniform, active and efficient sup¬
port with counsels and with money, which the State of Maryland has
extended to that great national work. The canal to Cumberland
may, and doubtless will, be completed in two years, and the
agricultural products and rich minerals unlocked by this great enter-
prize, be found floating on its bosom to tide water at Georgetown.
The citizens of Baltimore wiU scarcely deprive those from the
western part of the State of Maryland of the advantage of her markets
or relinquish herself the benefits—so certainly to be conferred upon
her or the citizens of the District, by the coal trade of Cumberland,
by longer delaying the commencement of a cross-cut canal.
If such a canal is not to be made, it may very pertinently be
asked, for what reason has the State of Maryland invested her funds
so liberally in aid of the Chesapeake and Ohio Canal?
A consideration of all the facts now before us, without reference to
any interests to be promoted or injured, leads directly to the conclu¬
sion that the route to Georgetown is that which any engineer would .
select on which to construct the shortestj cheapest, and most capacious
canal, to connect the harbour of Baltimore with the Chesapeake and
Ohio Canal. A glance at routes 3 and 4 in table III. wiU bring any
individual to this conclusion.
the relative distance to Georgetown and Baltimore, and that he was
24
An inspectinn of table III, and a comparison of routes No. .3 and
6, will as readily and clearly convince ony one that, the cities of the
District out of the question, the route from mouth of Seneca to Bal¬
timore through Georgetown, for the purpose of transporting burthens
in the cheapest and most expeditious manner, is decidedly better than
that of No. 3 through the Seneca and Patuxent vailles, though there
were less disparity in the cost of the two.
Let the relative expense of transporting one ton of coal from the
mouth of Senaca to Baltimore by both routes, be computed.
We suppose the rate of travelling on each route to be 3 miles per
hour, and that the passage of each foot of lockage will occupy one
minute—then the time of travelling each route will be as follows, viz.
Route No. 3, 76-^ 3=25.20 Î ^ minute.
701—60=12.41 )
Route No. 4, 67f+ 3=22.35 ) _2g
431 —60= 7.11 )
Difference, . . - 8 hours 15 minutes.
Showing the time of travelling the Senaca route to be 8 hours 15
minutes longer than through Georgetown—or 27-j'-g per cent, longer
time. Hence if the freights cent per ton per mile, on the route
irom Seneca to Baltimore through Georgetown, they would be on the
Seneca route, tVAV P^rts of a cent per ton per mile.
Then the relative expense, including tolls and freight for transport¬
ing one ton of coal by both routes to Baltimore, will be as follows—
as also the expense of transporting the same from Georgetown to
Baltimore.
Table IV.
Length in
miles.
Lockage
feet.
Tolls per
mile.
Freight
per mile.
Total expense.
Seneca route.
76
761
è cent
6 3 8 6
iVtt cents.
Georgetown route.
67i
431
i cent
5 00 0
iTTo 00
A7 7 5 <(
i^ry
Georgetown to
Baltimore,
43Î
262
h cent
5000
lïïo'ôo
44 7 5 tt
^^100
Shewing a difference of 18| cents per ton on coal, in favor of the
route through Georgetown, and 44 3-4 cents to transport one ton of
coal from Georgetown to Baltimore.
But it will be asked "is it not better to construct a canal on route No.
3, which will direct the trade to Baltimore, ere it reaches Georgetown.'"
Certainly, if such a canal would divert the trade. Let us take an
example—A boat descending the canal arrives at the mouth of Sene¬
ca. It would be an extravagance to suppose that the owner of this
boat could be kept in ignorance, even if he were previously so, of
25
the fact that he was but 23 miles from the latter, and 76 miles from the
former. Would the owner of this boat, with this knowledge, take
the Seneca route to Baltimore, unless there were strong inducements
of some kind to draw him there? And supposing such inducement did
exist; that it was to his interest to dispose of his cargo in Baltimore;
would these same inducements, operating upon him at the mouth of
Seneca, become impaired b). his passage through Georgetown ? In
a word, if the markets were equally good, a cargo at the mouth of
Senaca would be taken to Georgetown and there disposed of. If the
markets at Baltimore were better, the cargo would still he taken
through Georgetown to Baltimore, as-a cheaper and more expeditious
route, than that by Seneca. This view of the subject is so clear that
we should disparage the understanding of the community by further
detail.
We have thus arrived at the conclusion that the preferable route for
a canal from the basin of Baltimore to the Chesapeake and Ohio
Canal and thence to Cumberland, is that to the District of Colum¬
bia—Its length and lockage and cost are less than any other ; its ca¬
pacity for the transportation of heavy burthens at the least expense
and tiie shortest time exceeds greatly that of any other, and its fa¬
cilities for future enlargement incomparably greater—^for while the
canal by Seneca will admit of no future enlargement, the one to
Georgetown can be inceeased to any desirable extent.
We win subjoin some remarks as to the relative advantages of Bal¬
timore and Georgetown, with reference to a communication with the
sea.
The position of the cities of the District on tide water, and at the
débouché of the Chesapeake and Ohio Canal, is supposed to confer
on them an advantage over Baltimore in the coal trade, and that of
other articles, from the circumstance of boats being compelled to en¬
counter additional time and expense in coming 441 miles further by
canal for the sole purpose of reaching Baltimore.
But there are two considerations which influence by natural causes,
the relative advantages of Baltimore and Georgetown or Alexandria.
1st. The facilities of reaching these cities from the west ; and 2d.
the facilities of going thence to sea.
These considerations should be weighed, on the supposition that
each city stands purely on its local merits, without ascribing any pre¬
sent advantage to Baltimore, from her wealtli, enterprise and es¬
tablished connexions in business, which may hereafter be possessed
by the others.
From Georgetown to the mouth of the Potomac, the distance is
about 125 miles—From Baltimore to the mouth of Potomac, the dis¬
tance is 100 miles.
The depth of water from Alexandria to the mouth of Potomac is
sufficient to carry out a frigate without her armament, or about 19
feet—^but owing to the intricacies of the channel at the Eettlebottom
shoals, it is not safe to carry out more than 17 feet, unless vessels are
4
26
towed by steamers. Sandy Point, about 30 miles below George¬
town, IS also a difficult pass—but there is undoubtedly depth of water
sufficient for all commercial purposes, from Alexandria to sea.
From Georgetown a greater depth than 14 feet has not been ob¬
tained, and this not constantly, even with great expense of dredging,
the channel being liable to fill up by a single flood of the Potomac.
The obstacles to the navigation of the Potomac river are its defi¬
ciency of width and circuitous course, making it almost impossible for
vessels to beat through the reaches, as they are termed—and a rare
occurrence for any ship to get out with the same wind.
Mount Vernon reach and Maryland reach present great difficulties
unless the wind is from the exact quarter to carry ships through. We
have understood that ships nave been detained in the Potomac, by
contrary winds, two weeks.
From Baltimore the egress to the sea is easy. The same wind
from several quarters will carry ships to sea; while the width of the
bay affords ample room for vessels to beat with facility against head
winds.
The difference of time in going to sea from Georgetown and Bal¬
timore, is probably three days, on the average, in favor of the latter.
If steamers are employed to tow vessels on the Potomac, this ad¬
vantage in point of time will in a great measure be neutralised, though
at a greater cost on the part of Georgetown.
■ It is believed, with ordinary favourable winds that vessels could
sail to the mouth of the Potomac from Baltimore, or at all events
from the Bodkin, as soon as they could reach the same point from
George town by the aid of steam tow boats.
The advantage possesed by Baltimore, in the greater facility of get¬
ting to sea with ships, will, in respect to the coal and coasting trade
be obvious—it is upon the number of trips which any vessel can make
that her profits depend, and no vessel would be willing to lose three
days in a voyage along the coast, with the risk of occasional detention
in the Potomac two weeks, when she could come to Baltimore three
days sooner.
But the unrivalled advantage possessed by Baltimore is in the now
well ascertained fact that navigation during the severest and most pro¬
tracted winter weather, can be kept open, and freed from any embar¬
rassments which would impair seriously the facility of going to sea.
This is effected by ice boats, which in ordinary winters are only
required to open occasionally a passage to the Bodkin, about 15
miles from Baltimore.
The use of ice boats from Georgetown, is, undoubtedly practica¬
ble, but with this serious disadvantage. The Potomac (freezing
earlier in winter and opening later in spring than the Patapsco) is
closed with ice nearly to its mouth. Hence the necessity of ice
boats traversing the whole length of the river; which if not absolute¬
ly impracticable, would hardly prove expedient, owing to the expense
attending its execution.
27
The foregoing facts, showing the decided superiority possessed
hy Baltimore in the facilities of ingress and egress to and from her
harbour, but especially during the winter season, lead to the infer¬
ence that importations of foreign goods will be made into Baltimore
when the'y cannot be introduced into the cities of the district. As a con¬
sequence of this, western produce will seek here, in preference, a mar¬
ket, where it can be sold to pay for dry goods and other articles re¬
quired for the western markets. For where purchases are made, sales
will be effected, if prices are equally high, as a natural consequence
depending upon the fixed principles which regulate all trade and in¬
terchanges.
If therefore, the way is open, Baltimore will become the great
mart to which western produce will be sent, to make payments,
directly or indirectly, through the usual changes and transfers of com¬
merce, for the merchandize which is required for the west, and which
we have shown can be imported into Baltimore at the earliest period
to accommodate the spring purchases.
With artificial communications to the GREAT WEST, open equal¬
ly to her as to her rivals, Baltimore may securely rest her prosperity
on the unrivalled advantage she possesses in a harbour open at all sea¬
sons of the year to foreign and domestic importations.
On this advantage, her greater proximity to the west, heir reputa¬
tion and enterprize, must Baltimore rely, for the prosperity which she,
in common with every Atlantic city, is aspiring to, and which doubt¬
less win be the lot of aU—sharing as they must with each other the
illimitable trade of the gigantic west—which it is not too much to say
710 one city could accommodate and which ere twenty years, will require
double the number of avenues now completed orprq/ecied to transfer
it to the cities on the Atlantic coast.
In conclusion, I deem it proper to remark; that much credit is
due to Mr. F. Harrison, for the energetic manner in which
he conducted tlie field operations, which his former experience
well qualified him to direct. And to Messrs. Wilson, Edes, Chiffelle
and Finley, levellers and surveyors, as also to the respectable young
gentlemen attached to the brigade. The activity and cheerfulness with
which duties were discharged by aU, even amidst the rigours of win¬
ter, are worthy of all imitation.
The maps, profiles, and discriptive memoir, illustrative in detail, of
the Linganore and Seneca routes, herewith presented, confer great
credit on Mr. F. Harrison, and on Messrs. Wilson, Edes, Chif¬
felle and Edward H. Harrison, for the promptness and neatness with
which they have been executed.
All which is respectfully submitted,
by your obedient servant, ,
ISAAC TRIMBLE,
■ Civil Engineer.