The Land Owner, November, 1873
Never satisfied until it has exhausted every resource of information and instruction for its readers, The Land Owner lays before them in this number a complete series of illustrations of the system of tunnels begun in 1864 and now rapidly approaching final completion, which supply this great city with the pure and refreshing waters of Lake Michigan. Our artist, never wearying with studies of the grand and curious, has been for weeks engaged in visiting the bowels of the earth, where, under several parts of the city, gangs of men are at work night and day in making excavations, in going down the aqueous depths of the shaft at the lake crib, and in climbing to the lantern of the water tower on the shore.
The Old Tunnel.
In connection, and before describing the new tunnels now in process of excavation, it will be interesting to go back to the origin of the system and speak about the early struggles of the city to obtain pure water.
Ground was first broken for the Lake Tunnel, March 17th, 1864. The various causes which led to the undertaking of this gigantic work, and compelled such an enormous expenditure on the part of the city, may be briefly stated.
Since Chicago became a city, its great want had been an abundant supply of water. This want became more and more pressing as the city increased from a mere handful of settlers to the teaming mart of the Western World. Unlike most other cities, and especially those of the East, the surroundings of the Garden City were no more elevated than the place where the city itself stood, and no flow of water could be secured from any direction whatever. Indeed, the Chicago river possessed no current, being a bayou setting back from the lake, its source on a precise dead level with its mouth.
The astonishing growth of the city, unparalleled in the history of the world, its increasing commerce and trade, combined river to render the currentless river a cesspool of filth. Miles of sewerage were constructed, which discharge their foul contents into the turbid waters. Hundreds of steam tugs and lake craft plowed its surface, and the refuse and offal from numberless slaughter houses and packing establishments in the vicinity of Bridgeport, on the South Branch, found its way into the filthy river. In midsummer, the stench emitted from this repository of a city’s offal became intolerable; its waters grew yhick and slimy, obliging the steam craft that plowed its surface to go far ot into the lake to fill their boilers with pure water.
The New Water-Tunnel—Sinking The Shaft On Illinois Street
The waters of Lake Michigan were contaminated and befouled by the influx, rather than current of the river, for a great distance from the shore. A short distance north of the mouth of the river, the engines of the city water works were at work, pumping this foul liquid into the reservoirs, from whence it found its way into every family in the city.
Another grievous evil of the old water system was, that as cold weather approached, millions of infinitesimal fishes sought the enclosure near shore, from which the water was pumped. In spite of every effort, these scaly minnows would enter the reservoirs of the city, and come come out in scores from every hydrant alive and swimming. This was the greatest annoyance of all and one that could not be brooked. Every drop of water drank in the city was highly flavored of fish, and one was obliged to look twice in his goblet to see that he did not swallow one alive.
This had been the precise condition of Chicago since it arose from the prairie to be the largest city in the western world. It was blessed with commerce; with unequalled resources and avenues of wealth; with railroads running to it from every quarter of the country, draining the bountifully yielding prairies, and pouring their products into its granaries and storehouses. Emigration flowed toward it with unchecked tide. Its people grew rich, its schools numerous; its magnificent churches could be counted by scores; its fine public buildings and private residences astonished the world. Its population increased enormously each year. And Chicago was great, prosperous, and happy, with the sole exception that it lacked the one great essential to vitality, to life itself and the life of its citizens,—pure water.
Early Agitation of the Water Question.
This state of things was endured quite submissively until the year 1863, when the citizens began to show a determination to have it ameliorated in some manner or an-other. The war was in progress, and the nation was too much excited for anybody to think of much else. Engineers, men of mind and ability all over the country, were turning their attention to the field. The pencil of the draughtsman was busy in outlining fortifications, bridging rivers and outwitting the rebel foe. The all absorbing topic was the war. Men of wealth opened their purses and gave to the common cause; patriotic ladies and children did their best to help it to a triumph. The prospects were indeed poor for any great outlay in any other direction. But still the local agitation was kept up, until finally different parties began to submit plaus and specifications for purifying the river.
Many of these devices were Yankee in the extreme, and not a few of them almost provoked a laugh. Perhaps the most elaborate if any was that prepared by Mr. Gindele, of the Board of Public Works. He suggested that the waters of the Calumet and Desplaines rivers be diverted into the Chicago river, by means of the feeder and the use of pumps. To this it was objected that the supply of water would be inadequate, while the adoption of the plan would involve the city in interminable and expensive chancery suits, the diversion of the current of the streams and of the canal seeming necessarily to encroach upon rights which had vested in the canal company, and in the owners of mill property and water privileges on the canal and on the running streams.
A second plan suggested was to build a series of intercepting sewers, similar in their nature to those which have lately been erected in the city of London, for the purification of the river Thames. These, it was thought by some, could be constructed along the margin of the river, as reservoirs for the filth passing within its borders and from the sewers, the contents thus received being emptied into the lake, or distributed over the country for purposes of agriculture. This suggestion had a theoretic value. The largest city of the world adopted it, at an enormous expense, but to the time of its consideration here no results had been deduced which would warrant a certainty of probable success. The expenditure of money would be very great, and the loss of time would be considerable, and on so great an experiment, which had not in itself a fair prospect of success, our people were unwilling to enter. A covered aqueduct was also proposed. This it was thought should be of the diameter of ten feet, to extend from the lake to the river, which it should enter at some point on the south side, a point at about Sixteenth st. being designated. To this plan it was objected, that the obnoxious matter being emptied into the lake so near the point whence the lake water would be drawn, it would be corrupted and increase rather than diminish the evil complained of.
About this time the ship canal bill was killed, a result feared by many of our citizens. It deprived them of all hope of relief in this direction, and gave an impetus to the Tunnel project, which shortly afterwards gained great favor among all classes. Every scheme as yet presented had proved untenable, and the desired end–that of providing an abundance of pure water for Chicago, -was quite as far off as ever. Only one point had been gained, and that was, the people had now become thoroughly aroused on the subject. The grand result shows what popular will and determination can accomplish.
A Tunnel Under Lake Michigan.
The inventive genius of our citizens, and particularly of the different members of the Board of Public Works, was now thoroughly aroused. Western determination was at work, and Teutonic pluck was resolved to unloose the bulldog’s grip. We had plenty of pure water constantly in our view, tantalizing as the fact may appear. It was true that Lake Michigan was quite as foul as the river, near its mouth, but at a certain distance from shore the water be. came as pure as Croton, cold and clear as crystal. The contaminating influences of the Chicago river possessed no power over the waters of the lake, at a distance of two miles from shore. Here, then, was an eternal reservoir, from which Chicago could derive pure water in abundance, long after the masonry of the Croton aqueducts should crumble. It was a glorious idea in embryo. How could this natural supply of water be appropriated and made to flow through the miles o pipes and numberless hydrants of the city? The water, to insure its constant purity, must be drawn from the lake, at a distance of at least two miles from shore, far beyond the murky influx of the river and the city sewers. It was a great problem, worthy of the mind of genius. And it was solved. Chicago possessed a mind and a man equal to the gigantic task.
To Mr. E. S. Chesbrough, the skillful and accomplished city engineer, belongs the cre dit of the original idea of constructing a tunnel, two miles in length, beneath the bed of Lake Michigan, which should literally tap the lake from the bottom, at that distance from shore, and through which pure water should be conveyed into the reservoirs of the city. No sooner had Mr. Chesbrough conceived the idea of a tunnel, than he proceeded to investigate the subject. He soon determined, in his own mind at least, that it was entirely feasible, and prepared plans for its construction, into which the other members of the Board of Public Works entered with a will.
On the 13th day of February, 1863, the amended city charter was approved, in which power was given to the city “to construct such aqueducts along the shore of Lake Michigan, or in the highways, or elsewhere in said Cook county, and to construct such pumping works, breakwaters, subsiding basins, filter beds and reservoirs, and to lay such water mains, and to make all other constructions in said county, as shall be necessary in obtaining from Lake Michigan a sufficient and abundant supply of pure water for said city;” “to extend aqueducts, or inlet pipes, into Lake Michigan, so far as may be deemed necessary to insure a supply of pure water, and to erect a pier or piers in the navigable waters of said lake, for the making, preserving and working of pipes or aqueducts.”
Congress sanctioned this action of the Ilinois State Legislature, January 16, 1864.
And so the Chicago Lake Tunnel became a tangible thing.
Examination of the Bed by the Lake.
Soon after the action of the State Legislature, but before its sanction by Congress, the bed of the lake was examined, with a view to test the feasibility of excavating the Tunnel. In the month of June, 1863, the City Engineer, with some scientific aid, commenced boring to ascertain the nature of the bottom. The experiments were made first. at some twenty feet from the shore. At about two hundred feet from the shore, the water being a little over twenty feet deep, there was blue clay underlying a sandy covering. These experiments led to others. Two scows were towed into the lake and secured by anchors. From between these a two-inch gas pipe was lowered until it rested on the surface of the earth, the top being two or three feet above the surface of the water.
Down this tube an auger was passed, both being capable of being lengthened by screwing additional parts to each. At three-quarters of a mile from the shore, the water being twenty feet deep, there was found a four-inch covering of sand and thirty feet of blue clay. One and three-quarters miles out, the water being thirty-one feet deep, the same substratum was discovered. Two miles and a quarter due east of the water works, near the site of the crib as at present located, the water, being thirty feet deep, was clear and cool. The earth was penetrated to the depth of thirty feet. Here was found a covering of sand and soft mashy clay, with a clay becoming more hard and compact as it was sunk into On June 16th, of the same year, the temperature of the water began to be tested. Its clearness was apparent, a small object being visible at a distance of eighteen feet, the water being thirty-six feet deep. On the surface, the thermometer showed, at three o’clock of the 16th day of June, sixty degrees, and at the bottom fifty-one and a-half degrees. These experiments continued to be carried on with the like result of exhibiting a clay substratum, the approach to the shore, however, showing a deeper alluvial deposit. composed mainly of sand.
Award of the First Tunnel Contract.
The result of the above experiments was the adoption of Mr. Chesbrough’s idea of building a tunnel under the lake, which they demonstrated to be entirely practicable to the minds of the engineers. The old methods of purifying the river, the compound sewers, ship canals, windmills, etc., were at once abandoned; and it is said that the Board of Public Works occasionally laugh at their own folly in once entertaining such plans, now that the correct one has been found. But it was only through such inquiry and examination—research deep and long—that the proper plan was at last obtained.
The necessary drawings and specifications were now prepared, under the never wearying eye of Mr. Chesbrough. Advertisements for bids for building the Chicago Lake Tunnel soon astonished the world, appearing in all the Chicago papers, and, as we believe, the New York dailies. Several letters containing “sealed proposals” or bids were soon received, which were opened on the 9th of September, 1868, in the presence of the Board of Public Works, and nearly all the several parties proposing.
Messrs. Dull & Gowan, of Harrisburg, Pa., gentlemen well known in the engineering world, although not the lowest bidders, were the only parties who made an unqualified proposal, taking all risks of soil, etc., upon themselves, and consequently the contract was awarded to them.
The contract for this gigantic work, pronounced by engineers of both hemispheres to be the greatest the world ever saw, and beside which the tunneling of the Thames was mere child’s play, was signed and sealed on the 28th day of October, 1863. The paper, which bound the contractors to undertake and complete the greatest project ever entered upon by men, and the city of Chicago to pay them for the same, together with the penalties of failure by either party, bears the signatures of James J. Dull and James Gowan, the contractors, and J. G. Gindele, Frederick Letz, O. J. Kose, and F. C. Sherman, Commissioners of the Board of Public Works, and specifies the completion of the work “on or before the first day of November, A. D. 1865.” As will be seen hereafter, the time fixed for the completion of the work proved to be far too carly. It was destined to be the work of years.
The New Water-Tunnel—Apparatus For Elevating The Earth At The Shaft.
A delay of about two months in the casting of the huge cylinders for the shore shaft of the tunnel, at Pittsburg, Pa., postponed the inauguration ceremonies until the 14th of March, 1861, on which day the first shovelful of earth was removed. These ceremonies were of an interesting character, every man participating in them feeling aware of the great undertaking upon which they were entering, and the disgrace which a failure would bring both upon themselves and the city. The ceremonies were witnessed by about one hundred gentlemen, among whom were Mayor Sherman, Messrs. Letz and Rose, of the Board of Public Works, Mr. B. S. Hayes, the City Comptroller, Messrs. E. S. Chesbrough, U. P. Harris, and a majority of the Common Council. The Mayor made a few remarks appropriate to the occasion, and then took the pick and broke the ground, amid the cheers of the, company.
Each of the gentlemen took a shovelful of earth and placed it in the wheel-barrow, which was taken away by Colonel Gowan, one of the contractors. The field was then abandoned to Messrs. Dull & Gow-an, and the work placed in their hands; the Board reserving the right to examine and criticise the operations as they progressed.
Sinking the Shore Shaft.
Messrs. Dall & Gowan, the contractors, now entered zealously upon their enterprise.
A shaft about nine feet in diameter was sunk, on the above site, a short distance from the shore of the lake. When the workmen had descended a short distance into the earth they encountered a bed of shifting quicksand, which for a time defied all efforts at excava-tion. It was originally intended to construct the shaft wholly of brick, running it down from the surface of the ground, to a depth of fifteen feet below the level of the bottom of the lake, but encountering the quicksand compelled the abandonment of this method. The contract was consequently deviated from, and the contractors were authorized to run down an iron cylinder of the same dimensions as the centre of the crib, as far as the bottom of the sand bed, about twenty-six feet. This inlet cylinder is nine feet in diameter, inside, and two and a quarter inches thick. It is cast in four sections of about nine feet in length. The great labor of sinking these sections will be apparent to all. From the bottom of these cylinders, twenty-six feet, the shaft was continued into the earth until it reached the depth of sixty-nine feet, being constructed of brick from the point were the iron cylinders cease.
This shaft is not unlike an immense well. It was destined to be the great highway through which the clay excavated from the Tunnel proper should be conveyed to the outer world, and much satisfaction was felt by the contractors when this bare commencement of their great work was accomplished.
Over the mouth of this shaft, a rough, temporary building was erected, large enough to contain a steam engine of great power, the office of the contractors, and the brick, cement, tools, etc., used by the workmen. An elevator was now constructed, which carried the miners up and down the shaft to their work, being propelled by the engine.
Stepping upon this platform, half a dozen hardy miners, carrying each his little lamp, pick and shovel, would descend far far beneath the view of the spectators to their labors in the bowels of the earth. The clay which they excavated was brought up the shaft in the same manner, and the brick, cement, etc., carried down.
At the bottom of the shaft water soon began to ooze in, and it became necessary to construct a pump, which was worked by the engine, and which kept it dry.
Excavating the Tunnel Proper.
At the depth of sixty-nine feet the workmen stopped, and the shore “shaft” was pronounced a success. Here began that nice engineering, which one of the editors of the London Times, who had visited the Tunnel, pronounced “the greatest of modern times.”
The point in the lake where the Tunnel should receive water had already been fixed, by means of soundings, and buoys marked the spot. An imaginary straight line was drawn, which the Tunnel was to follow from the point where it crossed the shaft, which was little less than prolonging a straight line nine feet in length, without deviation, until it reached some point two miles ahead. The compass, the natural reliance of man upon the lake, could not be relied upon under the lake. Local attractions of earth would render it uselessly inaccurate, so far as giving anything more than a general direction was concerned. The only method of procedure was to run the axis of the Tunnel parallel with the straight line drawn over the lake, which was only observable at the point where it crossed the shaft.
With this, to less scientific minds than those engaged in the great work, frail reliance, the miners struck their picks into the hard clay at the bottom of the shaft, and excavating was commenced directly lakewards. The clay was thrown upon the elevator before mentioned, and drawn up the shaft, while an ingenious apparatus was arranged which carried it off and “dumped” it.
The width of the Tunnel, when bricked up, was decided to be five feet, and its clear height five feet two inches, the top and bottom arches being semi-circles. Two miners were all that could work upon the excavation ahead of the masons who laid the brick, and they were relieved at regular intervals, so that the work should not stop for a moment. The brick masonry, which followed the miners as fast as they advanced, was eight inches thick, the brick being laid lengthwise of the Tunnel, with toothing joints, to give it greater strength and durability. Between this masonry and the sides of the excavation, as much of the earth was forced back as possible. The lower half of the bore was constructed in such a manner that the bricks lie against the clay, while in the upper half the bricks were wedged between the brick and the earth, thus preventing any danger which might result from the tremendous pressure which it was feared might burst in the Tunnel.
The material used in the masonry was white Illinois brick, of the usual size, laid in cement. The Tunnel was to have a slope from the “crib,” or lake terminus, to the shore, of two feet to the mile, to admit of its being emptied in case repairs should at any future time be necessary, the water being shut off by means of gates at the lake end.
In this slow and tedious manner, the workmen made their way under the lake, from fourteen to twenty feet being considered great progress for twenty-four hours, the work being continued night and day. Before they had advanced far from the shaft, the air began to grow impure, and each day the difficulty increased. Here was an obstacle of no small moment to encounter. A large steam bellows was obtained, and placed at the mouth of the shaft, from which piping, not unlike ordinary stove pipe, was run down the shaft, branching off into the Tunnel. This tube was perforated with holes. in such a manner that the operation of the bellows extracted the impure or dead air from the Tunnel, causing pure oxygen to fill its place, which in turn was carried off by the pipe, when it was consumed by the lungs of the workmen. As the Tunnel progressed, this pipe was lengthened, and thus a constant supply of pure air was obtained.
Soon it became necessary to provide some more rapid means of transporting the earth from the face of the excavation to the shaft. Rails were laid down, and small cars placed upon them. At the commencement these cars were propelled to the shaft by workmen, where they were drawn up, and their contents discharged. But as the distance in-creased, day by day, and new lengths of rail were added, other means of locomotion were sought. Much to the edification of laborers, two small mules were purchased, which could barely stand between the walls of the Tunnel without rubbing their ears. After some little schooling, these tractable animals were placed upon the elevator, and lowered into the earth. After a little experience and training, they learned their work, and performed it well.
Several cars at a time were now loaded, and the mules attached, which drew them to the shaft. A regular time-table was pre-pared, to avoid collisions, as it was impossible for any person entering the bore to pass the “down’ train, should he be so unlucky as to encounter it in the bowels of the earth. At the shaft, the mules were turned around, and the train of empty cars drawn back. These mules and their long train of cars presented a very picturesque appearance, each of them wearing a small lamp upon his collar, which served for the calcium light before the engine. This submarine railroading will be further spoken of in another place.
When the Tunnel had reached the distance of one thousand feet from the shaft, a sort of chamber or stopping place was made, where the excavation was enlarged, to afford a deposit for the material used, a place to mix the cement, turn-tables for the cars, stables for the mules, etc., as seen in the illustrations. These we left at the distance of one thousand feet apart, to be bricked up when the whole work was completed. The distance was marked upon the inside of the bore, as fast as the work progressed from the shaft, every five feet.
The Crib and Its Successful Launch.
The “crib,” as it has been commonly called, was built on shore, and launched, much like the Great Eastern or any other sea going hulk. It was composed of huge timbers and tons of iron, no expense being spared to make it strong; it was forty feet six inches high and built in a pentagonal form, in a circumscribed circle of ninety-eight and a half feet in diameter. It was constructed with three walls—the outer, the center, and the inner—making it almost like three distinct structures, one inside the other, and all firmly braced or bolted together, so as to constitute one great structure. Each of these walls was caulked and tarred, like the hulk of a vessel. They were constructed of twelve-inch square timber, the first twelve feet from the top of white oak, and the remaining twenty-eight feet of white pine. Each piece of timber comprising either wall was firmly bolted in its place with square rods of iron, one and five-sixteenths of an inch in diameter and thirty inches long. The bottom was composed of twelve-inch timbers, held in place by bolts thirty-six inches in length, passing through three distinct layers of timber. The whole framework was a combination of massive timbers and irons, irmly held together by bars and bolts and braced in every direction. In the center was “well,” open at the bottom and top, through which the shaft was to descend into the bottom of the lake.
The Crib, Or Lake End Of The Tunnels, Where The Pure Water Is Taken From The Bottom Of Lake Michigan, Two Miles From Shore.
Each angle of the crib was provided with iron armor, to protect it from ice or any other body borne upon the waves. This covering was of iron two and a half inches thick, and covered the structure two feet each way from the angles, and extended downwards from the top twelve feet. This armor was fastened to the outer wall of the crib and the adjacent timbers by iron bolts thirty inches long, and to the inner wall and its timbers by round iron bolts, an inch and a half in diameter and thirteen and a half feet in length.
That people may form a correct idea of this immense structure, and the importance it possessed in the great work, we give a few items of the timber and iron used in its construction. It cost not far from one hundred thousand dollars before it was moved from the stocks. Reduced to board measure, there the stocks. were used in building it 618,885 feet of lumber, as follows:
Besides this, there were used flve hundred bales of oakum and sixty-five tons of iron bolts.
This immense structure was built like a vessel, on the north pier, a short distance from the mouth of the river. On the 24th day of July, 1865, an immense concourse of people gathered on the spot to see it launched. So great was the interest felt in its being successfully put in position, that merchants left their counting-rooms and hurried to the scene. Thousands of people were present, standing upon the house tops, riding upon the river in yawls, and seated in carriages upon the banks and piers.
The launch was announced to occur at between nine and ten o’clock in the morning. The day was propitious, scarcely a ripple breaking the surface of the lake. From the summit of the crib floated American flags, and the hat of Col. Gowan was occasionally visible, as he went to and fro, giving orders to the workmen. The river itself presented a lively appearance.
Seven tugboats, with flags, flying and hundreds of people on their decks, among whom were Governor Oglesby, of Illinois, and many other distinguished men, were waiting in the harbor to tow the monster to its place in the lake.
Shortly after ten o’clock, the leviathan moved, rode slowly into the river, with streaming flags, and the hat of Col. Gowan swinging over his head from the top. Cannon boomed. hundreds of steam whistles shrieked, bells rang, and thousands of throats cheered lustily. When about in the middle of the river, the mass left the ways upon which it rode, and rose upon the water as gracefully as any craft that ever was launched.
The tugboats now attached their hawsers, and the crib was towed slowly towards the buoys in the lake, which had been placed there to mark its position, on a direct line with the shore shaft. These were reached at two o’clook p. m., and the hawsers out loose. The gates of the crib were opened as soon as it was in position, and it settled majestically into the lake, where it is ever more to remain, a monument of mind over matter.
When the crib was in place it was filled with stone, with the exception of the centre compartment, reserved for the lake shaft to go through, and oables were attached to its corners, which were fastened to the bottom of the lake by means of Mitchell’s marine mooring screws, never before used except in tunneling the Thames. The screws had previously been imbedded in the bottom of the lake.
The next end to be obtained was sinking the cylinders in the crib, in order that tun neling could commence in both directions. The winter of ’65 was at hand. A large quantity of brick and mortar were taken out piled upon the orib, as well as provisions for the men; it being anticipate that when the winter set in, the ice would not permit of reaching the crib for months at a time.
The New Water-Tunnel—Workmen Descending The New Shaft At Illinois St.
The New Engine At The Pumping Works.
Sinking the Lake Shaft.
The huge iron cylinders, which were to form the lake shaft of the Tunnel. were at length got out upon the crib, after much vexatious delay and expense to the contractors. These cylinders are nine feet in diameter. and the iron is two and a half inches thick. They were cast at Pittsburg, Pa, in nine. feet sections, their immense weight rendering it otherwise impossible to move them. The end of each section was provided with a heavy flange, through which it could be bolted to the one below it, similarly constructed. These cylinders are seven in number, their respective weight being about eleven tons. The irons used in bolting them together were one and a half inch, cemented as well as riveted in their places.
These immense cylinders once placed upon the crib, the next step was to get them in place in the center compartment of the structure. Mr. Bramhall, one of the engineers, solved the problem, inventing machinery and tackle for the occasion. The cylinders were partially suspended over the chasm in the crib by this tackle, then swung upon ways and supports of timber, in which manner they were at last placed in position and firmly riveted together.
After reaching the bottom of the lake, on which the crib rested, being sunk into the clay several inches by its immense weight, these cylinders, or sections of the shaft, were sunk into the ground twenty-seven feet, in much the same manner as the shore shaft was built, at which distance they reached the required depth, leaving a fall of two feet to the mile in a straight line drawn to the bottom of the shore shaft.
A complete shaft in the lake was thus formed, by means of the crib. The work now resolved itself into simply this: An island (the crib) is situated in Lake Michi-gan, two miles from shore, upon which (to draw a homely illustration that all will understand) are confined a number of convicts. There is no means of their escape to the city over the surface of the water, and they resolved to go under it. Never dreaming of this trick, the authorities have placed in their hands picks and spades, with which to till the island whereon they are confined for life. The villains go to work, dig a hole in the island until its bottom is below the bottom of the lake, then strike off for the shore. which they succeed in reaching after years of toil, much to the surprise of every body. This is the plan of the Tunnel, the crib forming an artificial island where the water is to enter, and pass to the shore, free from the impurities of the river or the oity sewers.
The lake shaft being ready, tunneling was commenced from the bottom towards the shore, on the first day of the New Year, 1866. The first brick at the crib end was laid on the 29d day of December, 1865. At that time the shore shaft had reached the length of 4.815 feet. The earth removed from the face of the Tunnel was carried up the shaft and dumped into the lake, and as it progressed similar appliances to the furtherance of the work were used to those already described at the shore shaft.
Scenes and Incidents Under the Lake.
It can easily be imagined that while the miners worked day and night, week after week, month after month, year after year, down in the bowels of the earth, directly under a large and ever restless body of water, that scenes and incidents occurred which would interest the world above ground, could they all be related with any sort of accuracy or coloring that would do them justice.
Veins of natural gas were frequently encountered by the mines, which often proved dangerous in the extreme. Becoming somewhat acoustomed to these froaks of nature, they at length began to treat them uniformly and with success. The sound of their picks as they struck them into the olay ahend, on the face of the excavation, told them when they were approaching a vein. When within a certain distance of it, they bored into the earth with an auger, pulling it out the instant the vein was struck and applying their lamp. The gas would instantly ignite, burn with a bright, clear flame, which light up the Tunnel for a long distance with a fitful glare. Some of these jets would burn several hours, obliging the workmen to leave the Tunnel, and await the extinction of the vein, when they would again proceed as before.
One day, while Col. Gowan was showing a party of visitors into the Tunnel, they distinotly heard the paddle wheels of a steamer, which just at that moment passed directly over their heads, on the lake, showing that the water and the earth were both good sound conduotors.
Returning to the outer world, they described the vessel steaming her way towards the harbor. The workmen frequently reported hearing similar sounds.
In September, 1865, a crevice was struck, through, which water began to drip into the Tunnel. The frightened miners fled in dismay, but soon returned, repaired the crevice, and proceeded with their work.
The New Water-Tunnel—Railroading And The Mule Train In The Tunnel.
The First Tunnel Completed.
On Saturdey, the 24th of November, 1866, the morning papers informed the citizens of Chicago that the two sections of the Tunnel bad progressed so not tomato o the dalthat them. The glorious result sent a thrill of joy to every heart, and the telegraph carried it to every quarter of the globe. The long anticipated time had arrived—the vexing question as to whether the two mining parties would meet, or, from some slight error of the engineers, pass by each other, and continue on tunneling at random, was answered. When it wis further announced that the sections had met each other to within the space of an inch, wonder at the grand result took the place of joy.
A new pumping engine, suficiently powerful to elevate into the reservoirs, from the Tunnel, eighteen million gallons of water in twenty-four hours, was purchased, which was placed in the new building. This engine, which at that time was the largest ever put up in the West, cost $112,350. It was built from designs drawn by Mr. Cregier, and is a model of beautiful machinery. Our illustration shows another monster engine since put up, and now in operation at the works.
Extensions Demanded—The New Tunnel.
But a year ago the original Tunnel was found to be inadequate to supply the rapidly growing city with water. Over such a great area had the city extended, that the supply in sections remote from the works was short, and occasioned great inconvenience. The Board of Public Works again set to work, and a now Tunnel, to act as a companion to the original one, is now being excavated. Mr. Wallis, in his sectional view of the water system of the city, has graphically shown this now “bore,” which runs along parallel with the old Tunnel, from the crib to the old pumping works, from whence it cuts under the entire city, to a point on the south branch of the river, to the lot recently purchased by the city of S. J. Walker, Esq., where the new pumping works are to be erected.
This tunnel under the city is now progressing rapidly. Shafts are sunk in several different localities, as seen in the sketohes, and the work is going rapidly forward. The method of excavating is similar to that employed in the old Tunnel, and fully described above:
The Completed System.
When this vast system is at length fluished, Chiongo will have the most perfect water works in the world, and certainly the most original and unique.
Our Water-Tunnels—Sectional View Showing The Entire Water System Of Chicago, From The Lake To The New Pumping Works, Corner Of Twenty-Second Street And Blue Island Avenue.