Popular Science Monthly/Volume 28/February 1886/Sketch of James B. Eads
JAMES B. EADS
SKETCH OF JAMES B. EADS. |
THE man who devised and furnished our Government with its first and most useful armored steamboats; who built the St. Louis Bridge; who made one of the shallowest mouths of the Mississippi River permanently navigable for the use of ocean-steamers, and who entertains other practical conceptions as grand as these which, by his logical presentation, have won the unqualified indorsement of the ablest of his professional brethren, has a most evident title to recognition in scientific biography.
James Buchanan Eads was born in Lawrenceburg, Indiana, May 23, 1820. "He very early," says Dr. Boynton, in the "History of the Navy during the Rebellion," "evinced such a love of machinery as attracted special notice." When only eight years old, he watched with the greatest interest all the machinery to which he had access. When nine years old the family removed to Louisville. The engine on board the boat excited so much admiration and wonder that the engineer was induced to explain to him the principal parts of the machine. So well did the lad profit by this one lesson in steam-engineering that in little more than two years after he constructed a miniature engine which was worked by steam. When about ten years old, his father fitted for him a small workshop, and there he constructed models of saw-mills, fire-engines, steamboats, steam-engines, electrical and other machines. One of the pastimes of his childhood was to take in pieces and put together again the family clock, and at twelve years he was able to do the same with a patent-lever watch, with no tools but his pocket-knife. When thirteen, misfortune overtook his father, and he had to withdraw from school and work his own way. His parents went to St. Louis in 1833 and he went with them. The steamer was burned in the night on the way there, and he landed barefooted and coatless, on the very spot now covered by the abutment of the great steel bridge which he designed and built. The only opening in the way of business that offered was to sell apples on the street, and by this means, for a few months, he sustained himself and assisted in supporting his mother and sisters. In time he obtained a situation with a mercantile firm, where he remained for five years. One of the heads of the house having an excellent library, gave him access to it, and he used his opportunity well to study subjects bearing upon mechanics, machinery, civil engineering, and physical science. In 1839 he obtained employment as a clerk or purser on a Mississippi River steamer. He again made the best use of his opportunity to acquire that complete knowledge of the great river which he was afterward able to turn to such good account in the noble enterprises he so fortunately carried into effect. In 1842 he constructed a diving-bell boat to recover the cargoes of sunken steamers. This was followed with a boat of larger tonnage, provided with machinery for pumping out the sand and water and lifting the entire hull and cargo of the vessel. A company was formed to operate this device, and it soon had a business that covered the entire Mississippi River, from Balize to Galena, and even branched into some of its tributaries. By his methods, a great many valuable steamers were set afloat and restored to usefulness which it would not previously have been possible to save, as they would have been buried very soon beneath the river-sands. It was while engaged in this business that he gained a thorough knowledge of the laws which control the flow of silt-bearing rivers, and of the Mississippi he was able to say years afterward that there was not a stretch in its bed fifty miles long, between St. Louis and New Orleans, in which he had not stood upon the bottom of the stream beneath the shelter of the diving-bell.
In 1845 he sold out his interest in this company and established in St. Louis the first manufactory of glass-ware west of the Ohio River. Two years later this enterprise culminated in financial disaster, and left him, at the age of twenty-seven, burdened with debts to the amount of twenty-five thousand dollars. He then returned to the business of raising steamers, removing obstructions from the channel, and improving the harbor of St. Louis. By the great fire of 1849, twenty-nine steamers were burned at the landing of that city, and most of these wrecks had to be removed by him. The capital with which he started again at this business was supplied by his creditors, and amounted to only fifteen hundred dollars. Ten years later he bad increased this modest sum to nearly half a million dollars, and had long previously paid off his creditors in full.
His first undertakings in this peculiar and instructive study of hydraulics occurred while he was constructing the first diving-bell boat, not then completed. A barge loaded with about a hundred tons of pig-lead was sunk upon the rapids of the Mississippi River, near Keokuk, in fifteen feet of water. A contract was made for the recovery of this lead. He had had no experience whatever with the submarine armor, or diving apparatus of any kind; but, engaging a diver from the lakes who was familiar with it, with an armor, an airpump, and a sailor skillful in the use of rigging, he started—at that time only twenty-two years of age—to the scene of the wreck. Obtaining a barge, this was promptly anchored over it, and preparations made for the diver to go to work; but the current was found so exceedingly rapid that it was impossible to use the armor with any safety. A belt around the diver's waist was attached by a cord to the bow of the boat to hold him against the current, and a ladder procured on which the diver undertook to descend, but it was impossible for him to control his body in the current. Determined not to be baffled, Mr. Eads immediately visited the town of Keokuk and purchased a forty-gallon whisky-barrel, with which to improvise a diving-bell. With several pigs of lead secured around one end of the barrel by a net-work of ropes, and with that head taken out, a block and tackle attached to the net-work at the other end, and a temporary derrick erected, he was soon prepared to commence the recovery of the cargo. But the diver demurred and would not descend in this dangerous looking apparatus. Mr. Eads then set an example which he has followed throughout all his varied experience as an engineer—which was, never to ask a man in his employ to go where he was unwilling to trust his I own life. The bell thus suspended was held against the current by a rope which led up to the bow of the barge, and a strap across the lower end of the barrel was used as the seat for the diver in it. He at once got into the diving-bell and ordered his men to lower him down. He had a trace-chain attached to a lead-line, the lower end of the trace-chain having a ring in it, and with this he was readily enabled to form a loop, which was placed over one of the pigs of lead, and at a given signal it was hoisted up. A small cord sufficed to draw it hack to him while he was still in the bell; and in this manner a number of the pigs, weighing seventy pounds each, were recovered before he started to come up—the air-pump all the time supplying him with air. But, in the mean time, having cleared the space beneath the bell, the guy-line moved it farther and farther up-stream, in compliance with his signals, and instead of the line being slacked out again when his men commenced raising the bell, it was held so far forward that the derrick capsized, having no guy to hold it in the opposite direction. His assistants seized the block and tackle and pulled the whisky-barrel up to the surface of the water by hand. But it was so weighted with the lead around it that they could not raise it higher. Not knowing what was the matter, he waited patiently, the air-pump running with redoubled velocity, supplying him with plenty of air. He soon saw the fingers of a man under the chime of the barrel, and, recognizing this as an invitation, he seized the man's hand and got out from under the barrel, much to the delight of all on board. The derrick was then secured against any possible catastrophe occurring again, and, after a number of successful trips to the bottom, the diver was content to do the remainder of the work.
In 1856 Mr. Eads made a proposition to Congress to keep the channels of the Mississippi, Missouri, Ohio, and Arkansas Rivers clear of snags, wrecks, and other obstructions for a term of years. A bill embodying his plans was passed by the House of Representatives, but failed in the Senate for want of action by that body.
In 1857 his health compelled him to retire from business, and four years later he was called upon to render the most signal and brilliant services to his country in its time of extreme need. It was on the 17th of April, 1861, three days after the surrender of Fort Sumter, when Attorney-General Bates wrote to him from Washington: "Be not surprised if you are called here suddenly by telegram. If called, come instantly. Under a certain contingency it will be necessary to have the aid of the most thorough knowledge of our Western rivers and the use of steam on them, and in that event I have advised that you should be consulted."
The dispatch came shortly after the letter. Mr. Eads went immediately to Washington, and, after consulting with the President and Cabinet, prepared the plan he was requested to submit to them for placing gunboats on the rivers, with suggestions as to the kind of boats best fitted for the service, and in regard to the location of batteries to be erected at several points on shore. Shortly afterward he was appointed, with Captain (afterward Rear-Admiral) John Rodgers, United States Navy, to carry into effect the recommendations which he had made, and at once to improvise three war-vessels for service at Cairo. These were the Conestoga, Tyler, and Lexington, and were the first of the large fleet that afterward covered the Mississippi River. The Quartermaster-General issued proposals soon after for the construction of seven ironclad gunboats. These were designed by Mr. Eads, and be undertook to build them in sixty-five days—a short enough time under the best of circumstances; but business was then disorganized and all industrial enterprises in a chaotic condition. The materials with which the work was to be done had to be manufactured. Yet these seven heavily-plated vessels of about six hundred tons each were all finished according to contract, and another one still larger, a snag-boat, was by alterations and heavy plating made ready with the others for their armament. "Thus one individual put into construction and pushed to completion within a hundred days a powerful squadron of eight steamers aggregating five thousand tons, capable of steaming at nine knots per hour, large, heavily armed, fully equipped, and all ready for their armament of one hundred and seven large guns. The fact that such a work was done is nobler praise than any that can be bestowed by words."[1]
In 1862 Mr. Eads was commissioned to build six more armored iron gunboats, four of which were much larger than any of the eight preceding ones. These were likewise after his own designs, four of them having two turrets each and the smaller ones one turret each. These turrets were a modification of the Ericsson turrets, the Government insisting upon these being placed upon them. He was, however, permitted to place one turret on each of two of these large gunboats, after his own design, and costing about thirty-five thousand dollars each, but on the written condition that they should be replaced by Ericsson turrets if they were not found satisfactory. The guns in these two turrets were worked by steam, and this was the first time in the history of artillery-practice when heavy guns were manipulated wholly by steam. These vessels all proved to be of lighter draught than had been stipulated, so that it was possible to add from half to three quarters of an inch to their armor; and three of them exceeded very considerably the contract speed. While these fourteen ironclads were under way, Mr. Eads also had the construction of four heavy mortar-boats and seven tin-clad or musket-proof boats. The kind of ironclads that Mr. Eads designed and constructed and the kind of work they did are recorded in the history of Grant and Halleck's campaigns, and of Farragut's capture of Mobile.
In the construction of a steel-arch bridge at St. Louis, on which he was engaged from 1867 to 1874, Mr. Eads had to deal with problems which had not before confronted an engineer. The central arch of this structure has a clear span of five hundred and twenty feet, and is pronounced, by the "British Encyclopædia," the finest specimen of metal-arch construction in the world. The side arches are five hundred and two feet each in span. All of the piers, in consequence of the shifting deposits beneath the river-bed, were sunk clear through to the bed-rock. This required them to be sunk much deeper than any piers ever built, and through a medium of the most treacherous character. New plans had to be devised to secure success. One pier, weighing forty-five thousand tons, was sunk to a depth of one hundred and thirty-six feet below high-water mark through ninety feet of sand and gravel; and another one, weighing forty thousand tons, to one hundred and thirty feet through eighty feet of deposit. The loss of life which occurred in the caisson of the east pier resulted from the fact that the situation at such a depth, with the air-pressure it was necessary to endure, was entirely new, and there was no recorded experience by which operations could be guided safely. The erection of the arches developed new problems. The arches had to be designed about two and a half inches longer than they are in their present position, because of the contraction which their weight causes throughout the arch. Each half of the arch was built out from the pier and suspended by guys passing through heavy masts erected on each pier, and the central tubes had to be specially fitted for insertion. The suggestion was made by his chief assistant to contract the tubes by boxing them up and covering them with iron. This Mr. Eads disapproved of, and devised telescopic tubes for the center of the arch which could be shortened by an internal right and left hand screw-plug, and afterward extended by powerful levers to rotate this plug, steel bands being also provided to cover the plug, flush with the outside of the tube, when the tubes were properly distended. During his absence in London, the chief assistant, confident of his ability to close them with ice, and, having been left with full authority, undertook to do so; but the attempt proved a failure after a trial of eight or ten days, and the telescopic tubes, which Mr. Eads had prepared, were then inserted without difficulty.
In an address delivered at the opening of this bridge, July 4, 1874, Mr. Eads revealed that confidence in his resources and investigations which probably furnishes one of the keys to the secret of his success in this and in his other enterprises. This secret consists in the fact that his courage is always equal to his convictions. Everything, he said, on this occasion, which prudence, judgment, and the present state of science could suggest to him and his assistants had been carefully observed in its design and construction; every computation involving its safety had been made by different individuals, thoroughly competent to make them; they had been carefully revised, time and again, re-examined, verified, until the possibility of error nowhere existed.
A similar confidence was displayed in his plans for deepening the mouth of the Mississippi by jetties, in which he was opposed by nearly all of the United States engineers, and by a commission of seven of them. The commission in 1874 proposed to avoid the bars by building a canal from Fort St. Philip to Breton Bay. Mr. Eads's plan was to make the river itself deepen a channel through them. Congress naturally inclined to adopt the advice of its official experts, but Mr. Eads had faith enough in his plan to propose to do the work at his own expense and wait for his pay until he had demonstrated its success. It was hard to get permission to make even the experimental application of his views thus so liberally proposed; but a bill was finally passed to allow him to attempt the improvement of the South Pass, the smallest of the three, and not the one he had selected, and the depth on the bar of which was only eight feet. The cost of the work was to be five and a quarter million dollars; only half a million was to be paid after a channel twenty feet deep by two hundred feet in width had been secured, another half million after a channel twenty-two feet deep, and other sums on the obtaining of channels of twenty-six and twenty-eight feet depth respectively; but, as a guarantee that the maintenance of the channel should not cost more than one hundred thousand dollars a year, the final million of the whole sum was to be withheld until a channel of thirty feet maximum depth had been kept throughout during twenty years. Congress, however, deeming these terms unnecessarily severe, with remarkable unanimity voted to pay him one and three-quarter million dollars in advance of his contract terms, after he had secured twenty-two feet depth.
The conception of the plan of the jetties was based upon a knowledge of the fact that the Mississippi River is a transporter of solid material, almost all of which is held in suspension by the mechanical effect of the current, and that the quantity of the matter which it is able to carry increases with the square of the velocity. The current of the river is caused by the fall of the water from a higher to a lower level; that is, by the force of gravity. The element which resists the current is the friction of its bed; this friction does not follow the law of solids, but increases or diminishes exactly as the width of the bed or wetted perimeter of its cross-section is increased or diminished: hence, if the stream be contracted, where it is too wide, to one half its width, one half of the frictional resistance will be gone, and the current will be more rapid, and therefore more able to carry a larger load of sediment. This it immediately takes up from its own bed and thus causes a deepening. The result of the application of the jetty system to the South Pass has been a triumphant justification of its author's views.
On the 8th of July, four years after he commenced the work at the jetties, the United States inspecting officer reported that the maximum depth of thirty feet had been secured throughout the jetty channel, and that the least width of the twenty-six-feet channel through the jetties was two hundred feet. The balance due Mr. Eads upon his contract was then paid to him, and the million that was to be held as security for maintenance was considered as earned, and placed at interest for his benefit. The current of the river has maintained this depth ever since. The cost of the jetties was about half of the estimated cost of the proposed canal.
Mr. Eads bad not commenced the jetties before he turned his attention to the improvement of eleven hundred miles of the Mississippi throughout its alluvial basin by the jetty system. On March 15, 1874, in a letter to the Hon. William Windom, chairman of the Senate Committee on Transportation Routes to the Seaboard, the first outline of this novel plan was suggested.
In his review of the United States Levee Commission, February 19, 1876, Mr. Eads said:
"By the under-charge theory of the Delta Survey Report, caving banks are attributed to the direct action of the current against them, by which strata of sand underlying those of clay are supposed to be washed out. This is not eorrect. If the water be charged with sediment to its normal supporting capacity, it can not take up more unless the rate of current be increased. Caving banks are caused wholly by the alternations in the velocity of the current. Alternations are inseparable from a curved channel, because the current in the bend is usually more rapid than on the point; but, if the channel be nearly uniform in width, the caving caused by the curves will be very trifling. And, in proof of this, many abrupt bends exist in the lower part of the river where the whole force of the current has set for years directly against them without any important caving of the banks. The bend at Fort St. Philip is a notable instance, the great difference in the width of the flood-channel constituting the real cause of the destruction and caving of the banks. This tends to great irregularities in the slope of the flood-line, and, consequently, great changes in current velocity by which a scouring and depositing action are alternately brought into very active operation. The whole of the river below the Red River proves this; caving banks are much less frequent there than above, because the flood width of the river is far more uniform. A correction of the high-water channel, by reducing it to an approximate uniformity of width, would give uniformity to its slope and current, almost entirely preventing the caving of its banks, and through its present shallows, which now constitute the resting-places for its snags, there would be a navigable depth, in low water, equal to that which now exists in its bends. By such correction the flood-slope can be permanently lowered, and in this way the entire alluvial basin, from Vicksburg to Cairo, can be lifted, as it were, above all overflow, and levees in that part of the river rendered useless. There can be no question of this fact, and it is well for those most deeply interested to ponder it carefully before rejecting it; for the increased value given to the territory thus reclaimed can scarcely be estimated.
Two years later, in a review of Humphreys and Abbott's "Report on the Physics and Hydraulics of the Mississippi River," published in Van Nostrand's "Engineering Magazine," Mr. Eads elaborated this plan, and combated the declaration that the bed of the river is formed of blue clay and will not erode unless very slowly under the effect of the current, and likewise exposed the fallacy of the declaration that there is no relation between the quantity of sediment carried in the water and the velocity of its current.
Mr. Eads thus clearly outlined, in 1874, 1876, and 1878, one of the most magnificent plans which hydraulic engineering has ever undertaken. It is not simply to save thirty thousand square miles of land as rich as the Delta of Egypt from devastating inundations, but to extend deep water from the Gulf of Mexico to the mouth of the Ohio, into the very heart of the Mississippi Valley, while permanently locating this magnificent channel by practically putting an end to the caving of its banks. During the period we have referred to, Mr. Eads delivered addresses upon this subject in the chief cities of the river, published elaborate essays in which it was fully explained, and defended it against all attacks, until finally, in 1879, Congress authorized the creation of a commission to consider this plan, which is known as the "jetty system." The "outlet system" and the "levee system" were also examined by it, and in 1880 it reported in favor of the "jetty system," and recommended its adoption by Congress in its report, February 17, 1880. Mr. Eads was a member of the commission for two or three years. During this period, several million dollars were voted by Congress to carry out the plan, which will be found described in the report referred to, as agreeing substantially with the quotations we have made. Two reaches of the river, Plum Point, twenty miles long, and Lake Providence, thirty-five miles long, were selected for improvement; the low-water depth in the first reach was only five feet, the other reach (four hundred miles below) had a depth of only six feet. The permeable contraction-works, constructed of piles and willows, which had been first used by Mr. Eads at the South Pass several years before, were put in position for one season in the period between two floods, and the effect produced by the works during the first flood that followed was simply marvelous. The depth was increased through the upper reach to twelve feet at low water, and through the lower reach to fifteen feet, and scores of millions of cubic yards of sediment were deposited between them by the checking of the current by the permeable works. Thus new shore-lines of an approximately uniform width were developed. In some places the deposit was thirty feet deep.
Mr. Eads was, during the time of this construction, in bad health, and for some time absent from the United States. Owing to the charge made by several prominent friends of the river (members of the Senate and House), that the commission had abandoned the leading feature of the system, the contraction-works, and had changed it to a costly system of bank-revetments, and the public declarations of Mr. Eads to the same effect, no further appropriations were made at the last session of Congress to continue this magnificent work; enough has been done, however, to show the entire practicability of the plan.
Mr. Eads claims that this system of improvement designed by him is, in several respects, wholly different from any ever before proposed for the treatment of a river; it is, however, only applicable to rivers flowing through alluvial deposits.
The grandest work, however, contemplated by Mr. Eads, is the ship-railway which he proposed to construct across the Isthmus of Tehuantepec, for the transportation of large ships fully laden from ocean to ocean. This he holds to be entirely practicable—because the railway can be built wherever the canal can, at one half the cost of the canal with locks, or one quarter the cost of one at tide-level; because it can be built in one third or one quarter of the time needed to build a canal; because four or five times the speed practicable on a canal can be secured; because more vessels can be carried in a day over the railway than through the canal; because the capacity of the railway can be increased to suit increased needs without disturbance; because it will cost less to maintain and operate it than to maintain and operate a canal; because it can be built and operated where the canal can not be; because more accurate estimates can be made of the cost and time needed for its construction; and because its location is the very best of all those which are proposed on the American Isthmus. It is not generally known, but it is nevertheless true, that the location of the ship-railway and that of the Panama Canal are about twelve hundred statute miles apart, the whole immense territory of Central America lying between the two. It is, therefore, far superior in climate and in position to any other location.
Besides these works, Mr. Eads has, at the request of the Governments and individuals particularly interested, examined and reported upon the bar at the mouth of the St. John's River, Florida, the improvement of the Sacramento River, the improvement of the harbor of Toronto, the improvement of the port of Vera Cruz, the improvement of the harbor of Tampico, the improvement of the harbor of Galveston, and the estuary and port of the Mersey, England. He was President of the St. Louis Academy of Science for two terms, and made an inaugural address in which was embodied a review of the recent achievements of science, and, in another, the present knowledge of the laws of light. In 1881 he made an extemporary address before the British Association at York, upon the improvement of the Mississippi, and also upon the Tehuantepec Ship-Canal, which were, by unanimous vote, ordered to be embodied in its report of the proceedings; and in June, 1881, he was awarded the Albert Medal of the British Society of Arts, in token of its appreciation of the services he had rendered to the science of engineering—he being the first American upon whom this medal had been conferred. It is now his purpose to devote the remaining energies of his life, until the scheme is an accomplished fact, to the prosecution of the Ship-Railway.
- ↑ Boynton's "History of the Navy during the Rebellion."