Transcriber’s Note
Italic text is indicated by _underscores_, boldface by =equals signs=.
Other Notes will be found at the end of this eBook.
ILLUSTRATIONS
OF THE
CROTON AQUEDUCT,
_BY_
_F. B. TOWER_
OF THE
ENGINEER DEPARTMENT.
[Illustration]
New-York and London:
Wiley and Putnam,
1843.
ENTERED according to the Act of Congress, in the year 1843, by F. B.
TOWER, in the Clerk’s office of the District Court of the Southern
District of New-York.
TO
THE INHABITANTS
OF THE
CITY OF NEW-YORK,
WHOSE ENTERPRISE IS STRIKINGLY EXEMPLIFIED
BY THE CONSTRUCTION OF THE
CROTON AQUEDUCT,
THIS BOOK
IS MOST RESPECTFULLY DEDICATED,
BY
THE AUTHOR.
PREFACE.
The _views_ which I have given of the important points on the line of
the Croton Aqueduct, are from sketches taken for my own satisfaction;
but the interest so generally taken in the work, has suggested to me
the propriety of presenting them to the public in this form. Having
been engaged in the Engineer Department during the whole of the
construction of the Aqueduct, my acquaintance with it would enable
me to present more of its details; but I have given those of the
construction of the Aqueduct, and a general _outline_ of the structures
connected with it, trusting that a more detailed description may
emanate from JOHN B. JERVIS, Esquire, who, as Chief Engineer, gave
_Plans_ and _Specifications_ for the work during its construction.
A description from such source, accompanied with detailed plans of all
the appurtenances of the Aqueduct, with the results of experiments
on the flow of water in the Aqueduct, would be a useful contribution
to the cause of science, a valuable work to Engineers generally, and
particularly so to younger members of the profession.
The history which I have given of the preliminary measures leading
to the accomplishment of this work, has been obtained, mainly, from
printed documents of the Common Council. I have also had conversations
with persons who were intimately concerned in some of those measures,
and trust that I have made the history sufficiently full to embrace the
leading steps which were taken.
The accounts of the Aqueducts of ancient Rome, and those built by the
ancient Romans in other parts of Europe, also that of the Aqueducts of
modern Rome, of Italy, France, &c., have been mostly obtained from the
French work of J. RONDOLET, in which the account of the Aqueducts of
ancient Rome is translated from the Latin of Frontinus.
For the account of the Aqueducts of Mexico and South America, I am
indebted, in a great degree, to “_Bradford’s Antiquities of America_,”
and “_Ewbank’s Hydraulics_.”
F. B. TOWER.
TABLE OF CONTENTS.
PAGE.
Aqueducts of Ancient Rome, 13
Principal Aqueducts constructed by the Ancient Romans in other
parts of Europe, 18
Aqueducts of Modern Rome, 28
Principal Modern Aqueducts of Italy, France, etc., 30
Aqueducts of Mexico and the adjacent States, 37
Aqueducts of South America, 40
Fountains, 47
* * * * *
History of the Progressive Measures for Supplying the City of
New-York with Water, 57
Of Plans Proposed for furnishing the City with Water and of the
Plan adopted, 69
Sources of the Croton River, 75
Flow of Water in the Croton River, Capacity of the Fountain
Reservoir, &c., 76
General Design of the Channel-way and Reservoirs, 78
General Construction of the Aqueduct, 81
Description of the Line of Aqueduct, 95
Appendix, 125
* * * * *
PLATES.
Aqueduct of Spoleto, Italy, 32
Sections of the Croton Aqueduct, 84 & 86
Entrance Ventilator, 88
Isometrical View of Culvert, 90
Tunnel and Gate Chamber at the head of the Aqueduct, 92
View above the Croton Dam, 95
Entablature over the entrance to the Aqueduct, 96
View below the Croton Dam, 98
Croton Aqueduct at Sing-Sing, 101
Aqueduct Bridge at Sing-Sing, 102
Aqueduct Bridge for Road-way, 103
Croton Aqueduct at Mill-River, 104
Croton Aqueduct at Jewell’s Brook, 105
Croton Aqueduct at Hastings, 106
Croton Aqueduct at Yonkers, 108
Croton Aqueduct at Harlem River, 110
View of the Jet at Harlem River, 112
Croton Aqueduct at Clendinning Valley, 113
Aqueduct Bridge at Clendinning Valley, 114
Plan of the Receiving Reservoir, 116
Isometrical View of the Distributing Reservoir, 119
“The radiant aqueducts
Turn their innumerable arches o’er
The spacious desert, brightening in the sun,
Proud and more proud in the august approach:
High oe’r irriguous vales, and woods, and towns,
Glide the soft whispering waters in the wind,
And here united pour their silver streams,
Among the figured rocks, in murmuring falls,
Musical ever.”
_The Ruins of Rome._
INTRODUCTORY CHAPTER.
AQUEDUCTS, FOUNTAINS, ETC.
A supply of pure and wholesome water is an object so essential to the
health and prosperity of a city, that it should form one of the leading
features of the public improvements which characterize its growth. The
advantages arising from it are so numerous, and the comforts so great,
that every effort should be made to accomplish it.
The means which have been resorted to for such purposes in almost
every city of importance in the Old World, are examples for us of the
_New_, and should induce us early to avail ourselves of that important
element of health. We contemplate with mingled emotions of wonder and
admiration, those works of art which were achieved by ancient Rome in
her palmy days of wealth and power, and among them we find that her
_Aqueducts_ hold a prominent place.
Among the ruins of cities whose history is shrouded in mystery on this
continent, we find provisions for bringing water from distant sources.
In the wilds of Central America, the persevering traveller finds
ruined cities buried in the depths of the forest, where nature is at
work covering and concealing them: among those ruins he tells us of
the _Aqueduct_. We find them also among the ruins of cities along the
western coast of South America. With such examples before us, we may
consider that by the construction of the Croton Aqueduct for supplying
the City of New-York with water has been secured an important measure
for the promotion of its growth.
Many cities of the United States have directed their attention to this
object, and some have been fortunate in finding a supply of water near
at hand, but others will look towards distant sources for a supply, and
will, ere long, resort to the construction of _Aqueducts_.
In the history of cities built in remote periods of antiquity, we
find mention made of plans for supplying water, and among remains of
those cities which are found at this day, are traces of Aqueducts. We
have accounts of Aqueducts constructed under the reign of Solomon,
and the remains of them still existing in Palestine, give evidence
of an extensive acquaintance with the principles of hydraulics among
the Hebrew architects. The Pools of Solomon, which are mentioned by
travellers who combine in their researches a regard for the arts
as well as the religion of Judea, are connected with a scheme for
supplying Jerusalem with water.
The vast expense incurred in the construction of Aqueducts by the
Ancient Romans, as well in Italy as in other countries of Europe,
proves the value that was attached by that people to a plentiful
supply of pure water, and the details of the plan of construction of
the different works, evince an acquaintance with the principles of
hydraulics which, at this day, is not generally accorded to them.
That they understood the principle that water seeks the level of its
source after encountering depressions in its conduit, is sufficiently
proved by instances, in works constructed by them, where the inverted
syphon of pipes was used in crossing valleys. That this plan was not
_generally_ adopted by them in cases where great expense has been
incurred to maintain the uniform declivity of the conduit over valleys,
may be accounted for perhaps by the want of proper material for the
construction of pipes. In cases where this plan has been adopted
leaden pipes were used, and since it is only within the last century
that iron pipes have been invented, we may reasonably conclude that
considerations of such a nature would have induced them to adopt the
more expensive plan of maintaining the general inclination of the
conduit by vast structures of masonry.
By substituting inverted syphons instead of maintaining a uniform
declivity in the conduit, would not give the requisite discharge of
water at the elevation of the _terminus_ of the Aqueduct, and perhaps
they preferred, rather than diminish this elevation of the supply
of water, to incur the expense of high structures across valleys.
The Roman Emperors, with all their power and the wealth which was at
their command, knew how to perpetuate the glory of their reign by the
erection of Temples, Palaces and other public buildings, and what
is more natural than to suppose that in the construction of these
Aqueducts, which were considered so essential to the public welfare,
they should encourage works of such architectural magnificence?
Whatever the reasons might have been for maintaining the elevation of
their Aqueducts over valleys by such expensive structures, we have no
right to charge them with the want of that knowledge which the plan of
_some_ of their Aqueducts clearly proves them to have possessed.
Trusting that it will be interesting to the reader, I shall present
an account of some of the principal Aqueducts built by the Ancient
Romans,--some of the modern Aqueducts of Italy and France; also of
Aqueducts in other parts of the world. This account might be enlarged,
to embrace a description of more of the modern Aqueducts of Europe;
but sufficient will be presented, it is thought, to interest without
detaining the reader too long in arriving at the principal object of
this work,--_a description of the Croton Aqueduct_.
A view is given of the Aqueduct of Spoleto, in Italy. The bridge
supporting this Aqueduct is remarkable for the slender form of the
piers and their great height; being only ten and a half feet thick
and two hundred and fifty feet high to the base of the arches. This
Aqueduct was built by the Goths, a people who gave a model for Church
Architecture which is much admired at the present day. It is said that
they borrowed the idea of the form of their arch from the opening
beneath an arbor of trees.
The plan of the bridge for the Croton Aqueduct at Harlem River has been
criticised on account of the small thickness of the piers as compared
with their height, and because they were not made piers of equilibrium;
that is to say, having their bases broader, so as to include the line
of thrust of the arches, so that if a portion of the bridge were
removed, the remainder of the arches and piers would maintain their
position. By the present plan the permanency of any one individual arch
may be considered to depend upon that of the whole structure.[1]
The Aqueduct of Spoleto, has been standing about eleven hundred years
and is still in a perfect state of preservation.
With proper care in preparing the foundations of the bridge at Harlem
River, there is no good reason to fear that it will be less durable
than that of Spoleto.
AQUEDUCTS OF ANCIENT ROME.
The largest and most magnificent Aqueducts of which we have any
account, were the work of the Romans; and the ruins of several of them,
both in Italy, and other countries of Europe, remain to the present
time monuments of the power and industry of that enterprising people.
For 440 years from the foundation of Rome the inhabitants contented
themselves with the waters of the Tiber, and of the wells and fountains
in the city and its neighborhood. But at that period the number of
houses and inhabitants had so augmented, that they were obliged
to bring water from distant sources by means of Aqueducts. Appius
commenced this scheme of improvement. About 39 years after him, M.
Curius Dentatus, who was censor with Papirius Cursor, brought water
from the neighborhood of the city of Tibur; and applied towards
defraying the expense, part of the sums taken in the spoils of Pyrrhus.
After them Lucius Papirius, Caius Servillius Cepion, Lucius Longinus
Crassus, Quintus Marcius, (who brought water to Rome from a spring at
the distance of nearly sixty miles,) Marcus Agrippa, Augustus, and
others, signalized themselves by their noble Aqueducts. Even Tiberius,
Claudius, Caligula, and Carracalla, though in other respects not of the
best character, took care of the city in this useful article.
In the remains of these ancient Aqueducts, some are elevated above the
ground upon a solid mass of stone work, or upon arches continued and
raised one above the other; other portions are subterraneous, passing
through deep excavations, and in many instances piercing through
mountains of rock; such is that seen at Vicovaro beyond Tivoli, where a
_tunnel_ of about five feet deep and four broad, pierces a rock for a
distance of more than a mile.
These Aqueducts were generally built of stone and covered by arches
or large flat stones. At certain distances vents were provided to
discharge the water from the channel-way; and cavities were formed,
into which the water was precipitated, and where it remained till its
mud was deposited, and ponds in which it might purify itself.
One of these Aqueducts was formed with two channels, one above the
other: they were, however, constructed at different periods; the most
elevated was supplied by the waters of the Tiverone, _Anio novus_, and
the lower one by the _Claudian_ water. It is represented by Pliny, as
the most beautiful of all that had been built for the use of Rome.
It was begun by Caligula, and finished by Claudius, who brought its
waters from two springs called Cœruleus and Curtius. Vespian, Titus,
Marcus-Aurelius, and Antonius Pius, repaired and extended it; it is now
called _Aqua Felice_.
The Aqueduct that conveyed the Aqua Neroniana to Rome, was built of
brick; this, as well as the former, was in some instances 70 Roman feet
high.
The Aqueduct that brought the _Aqua Marcia_ into the city was repaired
by Agrippa, who laid pipes from it to several parts of the city.
The _Aqua Marcia_, _Aqua Julia_, _Aqua Tepula_, entered Rome in one
and the same Aqueduct, divided into three ranges or stories; in the
uppermost of which flowed the _Aqua Julia_, in the second the _Aqua
Tepula_, and in the lowest the _Aqua Marcia_. This accounts for the
extraordinary height of this Aqueduct, which far surpassed that of any
other in Rome. From the ruins of this fabric, which are still seen, and
are called “_Il castel del Acqua Marcia_,” it appears to have been a
very superb structure.
The Aqueducts were under the care and direction, first of the censors
and œdiles, and afterwards, of particular magistrates called “Curatores
Aquarum,” instituted by Agrippa, to whom the Aqueducts of Rome were
objects of particular attention. Messala was one of these curatores in
the reign of Augustus, and Frontinus held the same office in that of
Nerva. Augustus caused all of them to be repaired.
Procopius reckons only fourteen Aqueducts in ancient Rome; but Victor
has enlarged the number to twenty.
Frontinus, a man of consular dignity, and who had the direction of the
Aqueducts under the Emperor Nerva, mentions nine. From other accounts
we are informed that nine great Aqueducts existed at Rome at the
commencement of the reign of Nerva. Five others were constructed by
that Emperor, under the superintendence of Julius Frontinus; and it
appears that at a later period the number amounted to twenty.
Frontinus, who had the superintendence of the Roman Aqueducts under the
Emperor Nerva, died A. D. 101. He gave an account of the Aqueducts,
which has since been translated into French by Rondolet. The following
table is made up of data from that work.
The table is arranged to show, _First_, the name of the water or
Aqueduct; _Second_, the era of its construction; _Third_, the length
of each Aqueduct in miles and decimals; _Fourth_, the cubic feet
discharged in 24 hours, and _Fifth_, the gallons in wine measure.
+--------------------+-----------+---------+------------+------------+
| | | | | |
| NAME. | ERA. | LENGTH. | CUBIC FEET.| GALLONS. |
| | | | | |
+--------------------+-----------+---------+------------+------------+
|1. Appian Aqueduct, | B.C. 312 | 10,3250| 3,706,575| 27,724,181|
|2. Old Anio „ | „ 273 | 36,6775| 8,932,338| 66,813,887|
|3. Marcian „ | „ 146 | 56,9417| 9,525,390| 71,249,917|
|4. Tepulan „ | „ 127 }| 14,2341| { 903,795| 6,760,386|
|5. Julian „ | „ 35 }| | { 2,449,386| 18,321,407|
|6. Virgin „ | „ 22 | 14,3116| 5,085,624| 38,040,467|
|7. Alsietina „ | A.D. 14 | 20,4526| 796,152| 5,656,016|
|8. Claudian „ | „ 49 | 42,1989| 9,356,817| 96,988,991|
|9. New Anio „ | „ 90 | 54,1644| 9,622,878| 71,979,127|
| | |---------+------------+------------+
| | | 249,3058| 50,378,955 | 376,834,379|
+--------------------+-----------+---------+------------+------------+
Some auxiliary supplies or feeders make the total length of the Roman
Aqueducts, at that period, exceed 255 miles.
The names of the Roman Aqueducts are taken from those of the River or
Lake which supplies them, or from the emperors who caused them to be
constructed. Frontinus gives the following as the origin of the name
_Virgin Aqueduct_: “It is called the Virgin (Virgo), because it was a
young girl who showed some veins to a few soldiers who were in search
of spring water. Those who dug followed these veins and found a great
quantity, and there is a painting in a little temple erected close by
the source representing this event.”
SOME OF THE PRINCIPAL AQUEDUCTS CONSTRUCTED BY THE ANCIENT ROMANS IN
OTHER PARTS OF EUROPE.
_Aqueduct of Nismes._
This is probably one of the most ancient Aqueducts constructed, out
of Rome, by the Romans. It is attributed to Agrippa, son-in-law of
Augustus, to whom that emperor gave the government of the country
becoming a Roman Colony.
Agrippa, flattered by the honors which he received from the inhabitants
of Nismes, made his residence there: he enclosed the town with new
walls, built baths, and probably the Aqueduct of the bridge of Gard
(“_pont du Gard_”) for bringing water to them.
This Aqueduct is nearly thirty miles in length, forming, in its course,
the figure of a horse-shoe. It brought water from the fountains of Eura
and Airan, situated in the neighborhood of the town of _Uzès_. The
bridge of Gard was about the middle part of the work, and the Aqueduct
terminated at Nismes.
This Aqueduct traversed a very mountainous country, piercing through
mountains and crossing valleys by means of arches upon arches,
forming magnificent structures entirely of cut stone. The Aqueduct or
channel-way is formed of stone throughout the whole length. The bottom
of the interior has a curved form, being an arc of a circle; the sides
are vertical, and the top covered with a flagging of cut stone, except
where it is under ground, in which situation the top is covered by
an arch of stone. The interior face of the walls and the bottom were
covered with a coat of plastering two inches in thickness, composed of
quick-lime, fine sand, and brick nearly pulverized. This coating has
now a tenacity and consistence equal to the hardest stone.
The size of the channel-way is the following: 4 feet wide and 5⅓ feet
high, except where the top is covered with an arch, in which case it is
7½ feet high in the interior.
The descent of the Aqueduct is 1 foot in 2500 feet, or 2-11/100 feet
per mile.
The water which flowed in this Aqueduct formed a deposit upon the
sides, of lime, until nearly half the channel was closed; this deposit
amounting to a thickness of 11 inches on each side. By the height of
this deposit it has been ascertained that the water flowed generally
with a depth of 3¼ feet.
The _pont du Gard_ is that part of the Aqueduct of Nismes which crosses
the deep valley in which runs the _Gardon_ or _Gard_. This part,
considered alone, is one of the noblest monuments built by the Romans
among the Gauls. It is composed of three ranges of arches one above
another. The first range, under which the Gardon flows, is formed by
6 arches; the second by 11, and the third by 35, all of which are
semicircular; supported upon piers of greater or less height.
The channel in which the water flows is upon the top of the third range
of arches, and is 160 feet above the water of the river. The whole
length of this bridge is about 900 feet.
The bridge of Gard having been broken down at the two extremities,
at a period very remote and uncertain, it is thought that this
destruction may be attributed to the Barbarians who invaded the country
of Nismes a short time after their first invasion, which is fixed at
the commencement of the fifth century, about the year 406, and it
is supposed that by this means they would deprive the inhabitants
of Nismes of the water furnished by the Aqueduct, and force them to
yield. But by this supposition, which is very probable, the water had
been running in this Aqueduct for more than four centuries; and this
structure which has been out of use during fourteen hundred years, is
still in such a state of preservation that it could be restored without
a very great expenditure of money.
THE ANCIENT AQUEDUCTS OF LYONS.
Nothing gives a better idea of the splendour of the city of Lyons under
the reign of the first Roman Emperors, than the remains of the ancient
monuments. We see there at the present day, remains of temples, of
palaces, of amphitheatres, of basins for mock sea fights, of baths and
of many Aqueducts, of which three were constructed under the reigns of
Augustus, of Tiberius and of Claudius, for conducting water to that
part of the ancient city situated upon the mountain.
The first and the most ancient of these Aqueducts, constructed by Mark
Anthony, brought the waters from _Mount-d’Or_, by means of two branches
which embraced that group of mountains.
The water furnished by the first Aqueduct having been found
insufficient, they constructed a second one to bring the water of the
Loire.
The third Aqueduct was built by the Emperor Claudius to furnish water
to the palace of the emperors situated upon an elevated mountain. The
Aqueducts built at this era are all of the same construction; that is
to say, from the plan and construction adopted by the Romans. A fourth
Aqueduct was also constructed for this city, but there is some doubt
whether it was built by the Romans.
AQUEDUCT OF MOUNT PILA.
This Aqueduct was built by Claudius, who was born at Lyons, to conduct
water to the emperor’s palace, situated on the highest part of the
city. The sources which supplied it, were in the neighbourhood of Mount
Pila, and they were brought into the main Aqueduct by branch aqueducts.
The main Aqueduct was forty miles in length; and adding the branches,
the length of the Aqueduct was forty-five miles.
There were 13 bridges of stone to support the Aqueduct across valleys
or over rivers, two of which were not built up to the plane of the
Aqueduct, but were crossed by leaden pipes which descended on one
side of the valley and, crossing the bridge, ascended on the opposite
side. In another instance the pipes descended and crossed upon a wall
of masonry and reached the opposite side of the valley. One instance,
where pipes were used, will give an idea of their general form: the
bridge was about 40 feet high and the perpendicular height of the
Aqueduct above it was 140 feet. Nine leaden pipes of about 8 inches
interior diameter and one inch thick were laid upon the inclined planes
and across the level part of the bridge; thus communicating with the
opposite crests of the valley.
These bridges which were constructed for the support of pipes, were
wider in the bottom of the valley and also half way up the inclined
plane, than they were for the remainder of the distance; and this
form has suggested the idea that the pipes of 8 inches diameter, when
they reached half way down the plane, separated, each one into two of
6 inches diameter which crossed the bridge, and converged into one
again half way up the opposite plane. But it may be supposed that they
continued of the same interior form throughout their length, and that
this extra width was made for the purpose of giving an opportunity to
fortify the pipes at the place where the pressure to which they were
subjected was the greatest.
_Construction._
They commenced the construction by making a trench in the ground of
sufficient dimensions for the masonry of the Aqueduct: upon the
bottom of this trench was laid a mass of masonry 1 foot thick, upon
which two walls were built, each 1½ foot thick and 5⅓ feet high, these
walls standing 2 feet apart, and surmounted by a semicircular arch of
a thickness of 1 foot and generally covered with earth 2 feet deep.
The interior had a coat of cement plastering, 6 inches thick on the
bottom and 1½ inch thick on the sides. The walls were constructed with
small stones from 3 to 6 inches in thickness, bedded in mortar so
that no spaces could be found between them. They avoided the use of
stones of greater thickness than 6 inches, because the walls built of
small stones, well filled with mortar, formed a mass more solid and
impervious than with larger stones, on account of the great quantity of
mortar used.
No bricks were used in the construction of the channel-way of the
Aqueduct.
Ventilators were constructed along the course of the Aqueduct 2 feet
square, and rising above the ground 2 or 3 feet. The Aqueduct when it
was above the ground, was supported upon a wall of masonry, and the
side walls of the channel-way had an increased thickness. When it was
elevated 6 or 7 feet above the ground, the foundation wall was six
feet thick; but when it had a greater elevation it was supported upon
arches and piers, and upon the elevation depended the span of the arch,
the thickness and height of the piers. The general declivity in the
channel-way, was 1 foot in 640, or about 8¼ feet per mile.
This Aqueduct supplied about 1,200,000 gallons of water in 24 hours.
The velocity of the water was about five times that of the water in the
Aqueducts of Rome.
This work was constructed at an immense expense, and in substituting
the “_inverted syphon_,” for high structures across valleys, there is
evidence of the intelligence and skill of those who had charge of the
construction.
A fragment of a pipe forming part of this reversed syphon, is
still preserved in the museum at Lyons, and an instance of the
Romans having laid pipes across the beds of rivers, is given by M.
Gautier, Architect, Engineer, &c., in his work called “_Traité de la
Construction des Chemins_,” published in 1778.
About 70 or 80 years ago, he was directed by Mr. Pontchartrain,
Minister of State, to repair to Rochefort, to conduct spring water to
the port from the fountains of the city, which were supplied from a
source, though quite insufficient for the city, in the neighborhood. In
his researches he discovered a good and copious source, at less than
half a league, but on the other side of the river, the Charente. Many
difficulties were presented, because at low water vessels might ground
upon the pipes and injure them.
However, Mr. Gautier proposed to lay down two leaden pipes, to preserve
a supply in case of accident to one, and to protect them by wooden
frames in an effectual way against injury, should vessels lay upon the
defence frames during low water. Mr. Begon, intendant of the Marine,
approved the plan, but it was finally rejected.
“Some years after,” says Mr. Gautier, “when I had charge of the roads
on the Rhone, and of many other works in the Province of Languedoc, and
while at Arles, I heard that a vessel had cast anchor in the Rhone,
opposite the city, to take some loading; but when the commander wanted
to sail again he could not raise the anchor. This fact attracted much
attention, and many people went to witness the singular circumstance.
The Captain, unwilling to lose his anchor, sent down a man, to find
what was the matter. The diver reported that the anchor was hooked
under something round, but he could not tell what it was. A capstan was
applied to raise it, which succeeded.
It brought up a leaden conduit pipe from the bottom of the Rhone,
which crossed it from the City of Arles, towards Trinquetaillade, over
a breadth of about 90 toises (576 feet) in a depth of 6 or 7 toises
(about 40 feet,) the deepest part of the Rhone. I saw some pieces of
this conduit of lead, 5 or 6 inches in diameter, about 4 lines (one
third of an inch) thick, in joints of 1 toise each soldered lengthwise,
and covered by a strip or sheet of lead of the same thickness covering
the first solder about 2 inches. The conduit was soldered at the
joints, 6 feet apart, by the same material, which made a swell at
that distance. On each joint were these words in relief =C. CANTIUS
POIHINUS. F.= which was apparently the name of the maker or architect,
who laid down the conduit pipe in the time of the Romans. I delayed
not to inform Mr. Begon, at Rochefort, of this discovery, because he
had always favoured my project of conducting water along the bottom and
across the Charente, which would not have been half so difficult as it
had no doubt been, to lay one across the Rhone where this was found.
Hence it may be believed, as I think now myself, that many things
supposed now-a-days to be new and never to have been previously
invented, may have been thought of long before, even in remote ages.”
Pp. 129, 130.
_Ancient Aqueduct of Metz._
This Aqueduct was built by the Romans when that city was under their
dominion; but it is difficult to fix upon the precise era of its
construction. It is said in the history of the city of Metz that the
Roman legions built roads in the year 70; but there is reason to
suppose that the construction of this Aqueduct, as well as that of
other important structures built by the Romans at Metz, belongs to a
time more remote, and that the date of the reign of the first emperors
may be the era when the legions of Cæsar occupied the country of the
Gauls.
The total length of the Aqueduct was 14 miles, and the fall for this
distance was about 73 feet.
The channel-way was 6⅓ feet high, by 3 feet wide, constructed with
stone masonry and having an arch over the top: the interior face of
the walls and the bottom was covered with a coat of plastering; 3
inches thick in the bottom, and 2 inches on the sides. From remains of
this Aqueduct which are now found at various points along its course,
it appears to have required many expensive structures for crossing
valleys; in one instance the Aqueduct bridge was 3,600 feet long, and
the greatest height was 100 feet. In constructing the Aqueduct over
these bridges, they formed it in two channels separated by a wall, and
each covered with an arch; thus they insured a supply of water across
the bridge by one channel in case the other required repairs.
_Aqueduct of Bourgas, near Constantinople._
Three Aqueducts exist in the valley of Bourgas, 8 miles from
Constantinople, for conducting water into the city. One of them
is remarkable for the beautiful architectural arrangement and the
solidity of its construction. It is 115 feet high, and was built under
the Emperor Justinian, A. D. 527. It has two ranges of arches, one
above the other, and the Aqueduct supported upon the second. These
Aqueducts are in some parts unlike those of Rome, which were formed on
a continuous line for many miles, with a regular inclination from the
source to the city, but are interrupted by reversed syphons. Instead of
crossing deep and wide valleys in the usual manner of stone structures,
the Aqueduct terminates on one bank in a reservoir or cistern, and a
pipe is laid from it down the sloping side of the hill to a stone pier
erected at a suitable distance; the pipe rises up the pier to the top
where the water is discharged into a small cistern nearly as high as
that in the reservoir. From the cistern, another conduit pipe descends
to the bottom of the pier, passes along the ground to a second pier at
a proper distance and rises to another cistern on the top of it, and
so on till it rises on the crest of the opposite bank, where the water
resumes its regular motion along the Aqueduct.
This plan was probably adopted with a view to avoid the expense of
constructing a bridge which should preserve the general inclination of
the channel-way; but it is difficult to imagine any advantage arising
from the construction of the piers, instead of laying the pipe along
the bottom of the valley.
_Modern Rome._
Rome is now supplied with water by three Aqueducts, being three of the
ancient works restored in modern times.
First, _Aqua Virgini_, called by Frontinus, Aqua Virgo, or _Virgin
Aqueduct_.
The trunk of the Aqueduct having been injured, the reparation was began
under the Pontificate of Nicholas V. and Sextus IV., and completed
under that of Pius IV. in 1568. This water supplies the beautiful
fountain Trevi, thus named from the three discharges issuing from it,
or from its being placed at the junction of three streets. The water
this Aqueduct furnishes is 2,322,762 cubic feet (14,168,848 gallons)
daily, discharging through 7 principal conduits, at 13 public and 37
other fountains.
Second, _Aqua Felice_. This is a part of the ancient water of the
Claudian and Marcian Aqueducts united with many others, and collected
under Sextus V. The daily quantity it furnishes is 727,161 cubic feet,
(4,435,682 gallons,) and supplies 16 public and 11 other fountains. The
Moses fountain discharges from this source.
The Pauline Aqueduct, called _Aqua Paola_, is the third of the ancient
works restored. The water is collected within the territories of Arcolo
and Bassano, and conducted along the ancient Aqueduct of Alsietina.
This was effected under Pope Pius V., and directed by Charles Fontana,
an eminent Hydraulic Architect, who constructed the great fountain
of S. Pietro-in-Montorio. Additional water was also taken from Lake
Bracciano by Fontana in 1694, under Clement X. The whole quantity in 24
hours is 3,325,531 cubic feet, (20,285,739 gallons,) about one third
of which goes to feed the fountains of St. Peters, and those of the
Pontifical Palace on the Vatican Hill; the rest is distributed among 8
public and 23 other fountains, as well as to 21 work-shops, (_usines_)
in St. Pancras-street.
An evidence of the durability of these old Roman structures is
furnished in this junction of water from Lake Bracciano by Cardinal
Orsini, under authority of Clement X., upon condition that a part of
the water should be used to feed a second fountain about to be built
in St. Peter’s Square at Rome, and the rest to be divided between the
Apostolic Chamber and the House of Orsini. From the lake the conduit
leads to the old Alsietina Aqueduct, in which it flows 20 miles to
the city, and it was found to be in so perfect a state when the trial
was first made after the restoration, October 13th, 1693, that all the
water which entered the old Aqueduct was discharged at Rome without any
loss, after its use had been suspended nearly 1000 years.
THE PRINCIPAL MODERN AQUEDUCTS OF ITALY, FRANCE, ETC.
_Aqueduct of Caserta._
This Aqueduct was built by the order of the King of Naples, Charles
III., for conducting water to his residence which he had at Caserta, a
town situated about fifteen miles north of Naples.
This Aqueduct was commenced in 1753. It is twenty-seven miles long,
from the sources which supply it to the gardens of Caserta. The sources
are at the base of the mountain called _Taburno_; the principal one is
called _Sorgente de la Sfizzo_; it is afterwards joined by streams from
many other sources, which are in the country called _Airola_.
These waters are all joined in one Aqueduct, crossing the river
_Faënza_, upon a bridge of three arches, built in 1753. Again, in
the valley of _Durazzano_, there is another bridge of three arches,
upon which the Aqueduct crosses the valley, passing over the river,
and extending from the mountain called _Santa Agata de’Goti_, to the
mountain of _Durazzano_.
This Aqueduct afterwards crosses a deep valley, which it meets between
_Monte-Longano_ and the hills _Tifata_, where ancient Caserta is
situated, about the place called _Monte di Gazzano_. The crossing
of this valley required the most important of all the constructions
connected with the work. It was accomplished by an Aqueduct bridge,
1724 feet long and 190 feet in height, composed of three tiers of
arches, one above another. The lower range has nineteen arches, the
middle twenty-seven, and the upper one forty-three; making in all
eighty-nine arches.
The labor of constructions under ground for this Aqueduct was more
than that above; it pierced through five hills or mountains, making an
aggregate length of tunnel of about four miles, and most of this was
through rock.
To give air and light to the channel, they made pits or wells; some of
which were 250 feet deep, 10 feet diameter at the bottom, and 4 at the
top.
_Aqueduct Bridge of Castellana._
This Aqueduct was built in connection with an ancient _Causeway_, which
led to _Civita-Castellana_.
This _Causeway_ was about 820 feet long and 32 feet wide; the greatest
height was about 130 feet. It was pierced in the middle of this extent,
by nine large arches; three of which were 86 feet span, and the others
were each 64 feet span. Above these arches of the bridge the Aqueduct
is built, the height of which is about 57 feet, and it is sustained
upon a series of arches of about 19 feet span each.
_Aqueduct of Montpelier._
This Aqueduct is one of the most beautiful works of the kind, which
exist in France. The length is about 3,200 feet; it conducts to
Montpelier the waters of _Saint Clement_ and _du Boulidou_. It was
built by M. Pitot, engineer and member of the Academy of Sciences. He
was thirteen years constructing it. This Aqueduct is formed by two
ranges of arches; those in the lower tier are seventy in number, and
each 28 feet span; the piers of these arches are each 12 feet thick.
The arches of the second or upper tier are much smaller, and are
arranged so that three of them come within the space occupied by one of
the lower arches. They are 9 feet diameter; their piers are 4 feet and
a quarter thick.
The greatest height of this Aqueduct is 90 feet.
It is constructed entirely of cut stone. The quantity of water
furnished by it is about 300,000 gallons in twenty-four hours.
_Aqueduct of Spoleto._
This Aqueduct was constructed in the year 741, by Theodoric, King of
the Goths, to communicate with the town of Spoleto, situated upon the
summit of a mountain. It is composed of ten grand Gothic arches
each 71 feet diameter, supported upon piers of 10½ feet thickness. The
middle arches which are over the river _de la Morgia_, are about 328
feet high.
[Illustration:
_Napoleon Gimbrede. sc._
AQUEDUCT OF SPOLETTO, ITALY.]
On the top of this bridge is the Aqueduct which carries the water to
Spoleto.
This structure was difficult to execute, and being built of a very hard
stone, remains entire at the present day.
The total length is 800 feet, and the breadth is 44 feet.
The greatest height of this bridge is 420 feet.
_Aqueduct of the Prince of Biscari._
This Aqueduct was constructed by the Prince of Biscari, in Sicily, at
his own expense, across the river Saint-Paul, the ancient _Symète_. It
conducts a pure stream of water to the estate of the prince, and at the
same time serves as a public bridge over the valley. This bridge is
composed of thirty-one arches, the largest of which, over the river,
is 90 feet span. This arch is of Gothic form, while all the others
are semi-circular. The bridge has two tiers or ranges of arches; the
roadway is upon the first range, and the channel for the water, upon
the second or upper range. The length of the bridge is 269 feet.
The height to the top is 120 feet. It is said that this magnificent
structure was accomplished in two years.
_Aqueduct of Arcueil._
The Emperor Julian built this Aqueduct to bring water to Paris, A. D.
360; it supplied the palace and hot baths, but was destroyed by the
Normans. It was above nine miles and a half long, and was entirely
under ground, except the stone arcade over a deep valley at Arcueil.
After its use had been suspended 800 years, a new and beautiful arched
Aqueduct was built by the side of the ruins of the old one, and its
final restoration to public use was completed in 1634.
Part of this ancient construction, consisting of two arches
substantially built, still exists, near the modern Aqueduct.
The Aqueduct bridge over the valley of Arcueil has twenty-five arches,
is 72 feet high and 1,200 feet in length.
In the interior of the Aqueduct on each side is a parapet which forms a
walk. On the outside along the whole line are various openings, called
_regards_.
This Aqueduct was thoroughly repaired in 1777; and fresh sums of money
have lately been devoted to the same purpose by the city of Paris. It
supplies 36,000 hogsheads daily.
_Aqueduct of Maintenon._
This work, had it been completed, would have been one of the most
remarkable of modern times. The project was one of the noblest
examples of the enterprise which characterized the reign of Louis
XIV., and had it been carried out would have presented a work equal in
grandeur to any of the kind constructed by the Romans. It was projected
by Vauban, and the work was commenced in 1684, but was abandoned in
1688.
It was intended to conduct water from the river Eura to Versailles;
a distance of over seventy miles; and it was also contemplated to
continue the work to St. Cloud and to Paris; had this been done it
would have been over ninety miles in length. It was intended to be
of a mixed construction; partly by a canal formed by excavations and
embankments, and partly by a channel of masonry.
One of the most remarkable structures connected with it, was the
Aqueduct bridge across the valley of Maintenon. This was designed to be
entirely of masonry, having three ranges of arches, one above another.
The length of this Aqueduct bridge would have been three and a quarter
miles, and the height from the lowest part of the valley would have
been 234 feet.
The whole number of arches designed for this bridge was 685.
Some of the piers and arches of the lower tier were constructed, but
have since been suffered to crumble and fall. Many deep valleys were
filled with embankments, and the canal was completed for a portion of
the distance, but the course of the work is now but faintly marked by
the remains of these structures.
_Aqueduct of Lisbon._
The site of Lisbon, as well as the ground in its vicinity, consists
chiefly of limestone and basalt, which render it necessary to obtain
good water, at about three leagues distance, for the beverage, and
other uses of the inhabitants. The source consists of several springs
that are near to the village of Bellas, and their produce is conveyed
to Lisbon by an Aqueduct, constructed of a kind of white marble, and
finished in 1738. In some parts its course has been excavated through
hills; but near to Lisbon it is carried over a deep valley, for a
length of 2400 feet, by means of several bold arches, of which the
largest has a height of about 250 feet, by a breadth of 115. The arches
being pointed have an interesting aspect, particularly when viewed from
below, the interior of the spacious vaults being not only majestic in
appearance, but reverberating every sound. The water flows through a
stone tunnel, or covered arch-way, about 8 feet wide, formed in the
middle of the structure; and on each side there is a foot-path, with a
parapet wall, having a sufficient width for two persons to walk. The
Aqueduct enters the town on its northern side, at a place called da
Amoreira, where it branches into several others, in order to supply the
different fountains, from which the inhabitants are supplied. Persons,
denominated _gallegos_, obtain a subsistence by selling the water,
which they procure at the fountains in small barrels, and afterwards
cry it through the streets.
_Aqueducts of Mexico and the adjacent States._
The people who, in remote times, inhabited the region of Mexico, were
advanced in civilization and in the arts; they had regularly organized
states and established forms of government, and their immense cities,
their roads, Aqueducts and other public works, give evidence of the
advanced state of the arts among them and their knowledge of the
sciences.
The location and great population of some of their cities required a
familiar knowledge of hydraulic operations to supply them with water;
and hence it would seem as if they had cultivated this department of
the arts equally with others, for some of their Aqueducts were of a
character that would have done honor to Greece or Rome. Nearly all the
ancient cities of Mexico were supplied by them.
“The city of _Mexico_, which was built on several islands near the
shore of the lake, was connected to the main land by four great
causeways or dikes, the remains of which still exist. One of these to
the south, the same by which Cortez entered, was nearly two leagues
long--another to the north about one league, and the third at the
west somewhat less. The fourth supported the celebrated Aqueduct
of Chapoltepec, by which water was conducted from springs, upon an
insulated hill of that name, at the distance of from two to three
miles.”
The Aqueduct of Chapoltepec was the work of Montezuma, and also the
vast stone reservoir connected with it.
This Aqueduct consisted of two conduits formed of solid mason
work--each five feet high and two paces broad--by which the water was
introduced into the city for the supply of various fountains.
Olid and Alvarado commenced the siege of Mexico by attempting to cut
off this supply of water, an enterprise which the Mexicans endeavored
to prevent. “There appeared on that side,” says De Solis, “two or three
rows of pipes, made of trees hollowed, supported by an Aqueduct of
lime and stone, and the enemy had cast up some trenches to cover the
avenue to it. But the two captains marched out of Tacuba with most of
their troops, and though they met with a very obstinate resistance,
they drove the enemy from their post, and broke the pipes and Aqueduct
in two or three places, and the water took its natural course into the
lake.”
Humboldt says, there are still to be perceived the remains of another
Aqueduct, which conducted to the city the waters of the spring of
Amilco, near Churubusco. This Aqueduct, as described by Cortez,
consisted of two conduits composed of clay tempered with mortar, about
two paces in breadth, and raised about six feet. In one of them was
conveyed a stream of excellent water, as large as the body of a man,
into the centre of the city. The other was empty, so that when it
became necessary to clean or repair the former, the water might be
turned into it; which was the case also with those of Chapoltepec, “of
which one was always in use, whenever the other required cleaning.”
The gardens of Montezuma were also adorned and nourished with streams
and _fountains_, and appear to have rivalled those of Asiatic monarchs
in splendour.
The ruins of the city of _Tezcuco_, which with its suburbs was even
larger than Mexico, and according to Torquemada, contained one hundred
and forty thousand houses, still betoken an ancient place of great
importance and magnificence. Without the walls, tumuli, the sepulchres
of the former inhabitants, may yet be observed, and also the remains of
a _fine Aqueduct_ in a sufficient state of preservation for present use.
Two miles from _Tezcuco_, the village of _Huexotla_, situated on the
site of the ancient city of that name, which was considered as one
of the suburbs of _Tezcuco_, exhibits signs of ancient civilization,
in the foundations of large edifices, in _massive Aqueducts_, one of
which, covered with rose-colored cement, still exists in a perfect
state, and in an extensive wall of great height and thickness. A
covered way flanked by parallel walls proceeds from the ancient city,
to the bed of a stream now dry, over which there is a remarkable
bridge, with a pointed arch 40 feet high, and supported on one side by
a pyramidal mass of masonry.
_Tlascala_ was furnished with abundance of baths and fountains, and
_Zempoala_, like the city of _Tezcuco_, had every house supplied with
water _by a pipe_.