Part 1

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.

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.