STEVENS, John, member of the Continental congress, born in New York city about 1708; died in May, 1792. He was the son of John, who came from England in 1699 at about the age of seventeen, studied and practised law, and became a large land-owner. The son settled in New Jersey, and was one of the joint commissioners for defining the boundary-line between New York and that colony in November, 1774. Resigning as a royalist councillor in June, 1776, he was, from 27 August, 1776, till 1782, vice-president of the council of New Jersey, presiding over the joint meetings of the two branches of the legislature. He was elected to the Federal congress in November, 1783, and oil 18 December, 1787, he presided over the State convention that ratified the United States constitution.-His son, John, engineer, born in New York city in 1748 or 1749; died at Hoboken, New Jersey, 6 March, 1838, was graduated at King's (now Columbia)college in 1768, and was admitted to the bar, but practised little. During the Revolutionary war he held several offices, among which was that of treasurer of New Jersey in 1776-'9, and at its close he married and resided in winter on Broadway, New York, and in summer on the island of Hoboken, which he then owned. His life was devoted to experiments at his own cost for the common good. In 1790 he petitioned congress for protection to American inventors, and his petition was referred to a committee, which reported a bill that became the law of 10 April, 1790, the foundation of the American patent law. He had begun experiments in the application of steam in 1788, and now continued them, having as his associates Nicholas I. Roosevelt and the elder Brunel, who afterward built the Thames tunnel. Toward the close of the century he was engaged with his brother-in-law, Robert r. Livingston, and Roosevelt, in building a steamboat to navigate Hudson river, the legislature of the state of New York having previously offered a monopoly of exclusive privilege to the owners of a boat that, complying with given conditions, should attain a speed of three miles an hour ; but their boat failed to achieve the required speed, and their joint proceedings were interrupted by the appointment" of Livingston as minister to France in 1801. In Paris, Livingston met Robert Fulton, and afterward was associated with him in establishing steam navigation. Stevens persevered, and in 1804 built a vessel propelled by twin screws that navigated the Hudson. The boiler was tubular and the screw was identically the short four-threaded screw that is now used. That it was a helix, his letter of 1804 to Dr. Robert Hare, of Philadelphia, shows. This was the first application of steam to the screw-propeller. The engine and boiler of this steamboat are preserved in the Stevens institute at Hoboken, New Jersey Mr. Stevens always upheld the efficiency of the screw and its great advantages for ocean navigation. Shortly after his death his sons placed the engine and boiler referred to in a boat, which was tried before a committee of the American institute of New York, and attained speed of about nine miles an hour.

It is remarkable that after 1804 no serious attempt was made for the practical introduction of the screw until 1837, when it was brought into use simultaneously in England and the United States. Still more remarkable is the fact that its introduction into use in England was by the Archimedian screw of a single thread, and in America by a multi-threaded screw on the outer surface of a cylinder; that the first was completely modified in the course of five or six years into the short four-threaded screw that was used by Stevens in 1804, and that in about ten years the multi-threaded screw was also replaced by the screw of 1804. In 1807, assisted by his son Robert, he built the paddle-wheel steamboat" Phoenix" that plied for six years on the Delaware. Professor James Renwick, who from his own observation has left the best description extant of Fulton's boat, the "Clermont," as she ran in the autumn of 1807, says that "the Stevenses were but a few days later in moving a boat with the required velocity," and that "being shut out of the waters of New York by the monopoly of Livingston and Fulton, Stevens conceived the bold design of conveying his boat to the Delaware by sea, and this boat, which was so near reaping the honor of first success, was the first to navigate the ocean by the power of steam." Fulton had the advantage of a steam-engine that was made by James Watt, while his predecessors were provided only with inferior apparatus, the work of common blacksmiths and millwrights. The piston-rod of the "Phoenix" was guided by slides instead of the parallel motion of Watt, and the cylinder rested on the condenser. Stevens also surrounded the water-wheel by a guard-beam. Among the patents that were taken out by Stevens was one in 1791 for generating steam; two in the same year described as improvements in bellows and on Thomas Savary's engine, both designed for pumping; the multi-tubular boiler in 1803, which was patented in England in 1805 in the name of his eldest son, John C. ; one in 1816 for using slides; an improvement in rack railroads in 1824" and one in ]824 to render shallow rivers more navigable. In 1812 he made the first experiments with artillery against iron armor. He then proposed a circular vessel, to be rotated by steam to train the guns for the defence of New York harbor. On 11 October, 1811, he established the first steam-ferry in the world with the "Juliana," which plied between New York city and Hoboken. In 1813 he invented and built a ferry-boat made of two separate boats, with a paddle-wheel between them which was turned by six horses. On account of the simplicity of its construction and its economy, this description of horse-boat continued long in use both on the East river and on the Hudson.

In February, 1812, shortly before the war with England and five years before the beginning of the Erie canal, Stevens addressed a memoir to the commission appointed to devise water-communication between the seaboard and the lakes, urging instead of a canal the immediate construction of a railroad. This memoir, with the adverse report of the commissioners, among whom were De Witt Clinton, Gouverneur Morris, and Chancellor Livingston, was published at the time, and again, with a preface, by Charles King, president of Columbia, in 1852, and by the " Railroad Gazette" in 1882. The correctness of his views and arguments contrast strongly with the answer of the commissioners on the impracticability of a railroad. At the date of the memoir, although short railroads for carrying coal had been in use in England for upward of 200 years, there was not a locomotive or passenger-car in use in the world. Stevens's proposal was to build a passenger and freight railroad for general traffic from Albany to Lake Erie having a double track, made with wooden stringers capped with wrought-plate rails resting on piles and operated by locomotives. He enumerates comprehensively the advantages of a general railroad system, naming many details that were afterward found necessary, putting the probable future speed at from twenty to thirty miles an hour, or possibly at from forty to fifty. He gives a definite plan and detailed estimates of the construction and cost. His plan is identical with that of the successful South Carolina railroad built in 1830-'32, the first long railroad in the United States, which has been described as "a continuous and prolonged bridge." The accuracy of his estimates was proved by the cost of Sis road. Stevens in 1814 applied to the state of New Jersey for a railroad charter from New York to Philadelphia. He received the charter in February, 1815, and located the road, but proceeded no further. In 1823, with Horace Binney and Stephen Girard, of Philadelphia, he obtained from the state of Pennsylvania a charter for a railroad from Philadelphia to Lancaster, on the site of the present Pennsylvania railroad. These two were the first railroad charters that were granted in this country. On 23 October, 1824, he obtained a patent for the construction of railroads. In 1826, at the age of seventy-eight, to show the operation of the locomotive on the railroad, he built at Hoboken a circular railway haying a gauge of five feet and a diameter of 220 feet, and placed on it a locomotive with a multi-tubular boiler which carried about half a dozen people at a rate of over twelve miles an hour. This was the first locomotive that ever ran on a railroad in America. Colonel Stevens was an excellent classical scholar, and not only a close student of natural philosophy, but fond of metaphysical speculations, leaving several philosophical treatises, which have never been published. He was through life an enthusiastic botanist and amateur gardener, importing and cultivating many new plants. The accompanying engraving represents Castle Point, Mr. Stevens's residence in Hoboken, New Jersey, which in 1835 was replaced by the present more spacious mansion.--The second John's son, John Cox, born 24 September, 1785; died in Hoboken, New Jersey, 13 June, 1857, was graduated at Columbia in 1803, and married Maria C. Livingston on 27 December, 1809. In the early part of his life he resided on his estate at Annandale, on the Livingston manor, and later in New York city. He was from his youth a devoted yachtsman. He organized the New York yacht club, was its first commodore, and commanded the "America" in the memorable race in England in 1851.-Another son, Robert Livingston, born 18 October, 1787; died in Hoboken, New Jersey, 20 April, 1856, having a strong engineering bias, began to assist his father when only seventeen years old. He took the "Phoenix" to Philadelphia by sea in June, 1808. At the death of Fulton the speed of steamboats on the Hudson was under seven miles an hour, and at about that date Robert L. Stevens built the "Philadelphia," which had a speed of eight miles. He built many steamboats, increasing the speed of each successive one up to 1832, when the "North America" attained fifteen miles. From 1815 until 1840 he stood at the head of his profession in the United States as a constructor of steam vessels and their machinery, making innumerable improvements, which were generally adopted. In 1821 he originated the present form of ferry-boat and ferry-slips, making his boats with guards encircling them throughout, and constructing the ferry-slips with spring piling and spring fenders. In adopting the overhead working-beam of Watt to navigation, he made important improvements, inventing and applying, in 1818, the cam-board cut-off, substituting in 1821 the gallows-frame that is now used for the column that supported the working-beam, and making that beam of wrought-iron strap with a east-iron centre, instead of purely of cast-iron. This he improved in 1829 into the shape that is now universally used. He lengthened the proportionate stroke of the piston, and invented the split water-wheel in 1826. In 1831 he invented the balance-valve, which was a modification of the Cornish double-beat valve, and is now always used on the beam engine. He placed the boilers on the wheel-guards and over the water, improved the details in every part, and finally left the American working-beam (or walking-beam)engine in its present form. At the same time he strengthened the boiler, beginning with a pressure of two pounds to the square inch, and increasing the strength of the boilers, so that fifty pounds could be safely carried. He made the first marine tubular boiler in 1831, and was among the first to use anthracite coal. In the hulls of his vessels he gradually increased the amount of iron fastening until it was finally more than quadrupled, increasing the strength of vessels while diminishing their weight. He reduced the vibration of the hull by the masts and rods that are now used, and added greatly to their strength by his overhead truss-frame On the opening of the Liverpool and Manchester railway in 1830, he went to England, where he had made, from a model he brought over, the rails for the road he was building, with his brother, Edwin A., in New Jersey. This rail is the well-known T-pattern, used in this country and in a large part of Europe, which is fastened by spikes without the intervention of chairs, which are required by the form of rail that is still used in England. He also then ordered from the Ste-phensons the locomotive called the "John Bull," the prototype of those that are made in this country, which is now preserved at the Smithsonian institution in Washington. Toward the close of the last war with England Robert was engaged in making a bomb that could be fired from a cannon instead of from a mortar, and that could thus be applied to naval warfare. In connection therewith he made many experiments on the Hoboken marshes, for which he obtained from the government the loan of heavy ordnance, and finally he succeeded in producing a successful percussion-shell. President Madison then appointed a board to test this shell in the harbor of New York, both against solid targets of wooden beams and against an actual section of a ship of the line, built for the purpose. Each was demolished by a single shell. The government then adopted the shell, purchasing a large quantity, together with the secret of its construction. In 1814 Edwin, under the direction of his father, had experimented with shot against inclinediron-plating, and in 1841, when, on account of the United States boundary disputes with England, public attention was directed to naval defences, he made a series of experiments, which he and his brothers laid before the government. President Tyler appointed a commission of officers of the army and navy to superintend, at Sandy Hook, the experiments of the brothers on the application of iron to war-vessels as a protection against shot, who, after many trials against iron targets, reported that iron four and a half inches thick resisted effectually the force of a sixty-four pound shot fired at thirty yards with battering charges. Thereupon an act was passed, 14 April, 1842, authorizing the secretary of the navy to contract with Robert L, Stevens for an iron-clad steam vessel. Stevens immediately began to excavate a dry dock for his vessel, which he had finished within a year, and also had his vessel planned, and began its construction; but the contract was changed in the latter part of 1843, when Commander Robert P. Stockton constructed a wrought-iron cannon having a bore of ten inches and throwing a round shot that pierced a four-and-a-half-inch target. At each successive important increase of the power of the gun, either at home or abroad, the increased thickness of armor necessary for defence required increased tonnage in the vessel that Stevens had contracted to build, causing interminable interruption and consequent delay. This vessel, which was known as the Stevens battery, lay in its basin at Hoboken for many years, and was never launched. It was the first iron-clad ever projected, preceding by more than ten years the small iron-clad vessels used by the French at Kinbum in 1854.--Another son, James Alexander, born in New York city, 29 January, 1790; died in Hoboken, New Jersey, 7 October, 1873, was graduated at Columbia in 1808, and admitted to the bar in New York city in 1811. In connection with Thomas Gibbons, he established the Union steamboat line between New York and Philadelphia, which led to the suit of Ogden vs. Gibbons, memorable for the decision that placed all the navigable waters of the United States under the jurisdiction of the general government.--Another son, Edwin Augustus, born in Hoboken, New Jersey, 28 July, 1795 ; died in Paris, France, 8 August, 1868, after assisting his brother Robert, in 1826 took charge of the Union line, which was shortly after merged into the Camden and Amboy railroad, the charter for which the two brothers obtained from the state of New Jersey in 1830. They prosecuted the work so vigorously that the road was opened for traffic on 9 October, 1832, the elder brother being president and the younger treasurer and manager. In the next twenty years the railroad system of the United States, differing materially from that of England, was formed, and in aiding this development the brothers were conspicuous, inventing and introducing many appliances on the road. locomotives, and cars. The germ of many improvements afterward perfected on other roads can be traced back to the Camden and Amboy. Of this the vestibule-car is a modern instance. The brothers, while engaged in railroad affairs, still retained their great interests in navigation, and made many improvements in it. In 1827 the elder brother applied forced draught to the "North America," and its use immediately became general, while in 1842 the younger patented the air-tight fire-room for this forced draught, and applied it on many vessels. This double invention of the two brothers is now used in all the great navies of the world. Both brothers spent a great part of their lives in devising and effecting improvements in the means of attack and defence in naval warfare. Robert had bequeathed the Stevens battery to his brother, and Edwin, at the beginning of the civil war. presented to the government a plan for completing the vessel, together with a small vessel, called the "Naugatuck." to demonstrate the practicability of his plans. This small vessel was accepted by the government, and was one of the fleet that attacked the "Merrimac." She was a twin screw-vessel, capable of being immersed three feet below her load-line, so as to be nearly invisible, of being raised again in eight minutes by pumping out the immersing weight of water, and of turning end for end on her centre in one minute and a quarter. The government refused to appropriate the money on the plans that were proposed by Mr. Stevens, and at his death he left the vessel to the state of New Jersey, together with $1,000,000 for its completion. He founded the Stevens institute (see illustration), bequeathing to it and to the high-school a large plot of ground in Hoboken, and $150,000 for the building and $500,000 for endowment.--His widow, MARTHA BAYARD, has devoted $200,000 to religious and charitable institutions, among which may be mentioned the erection of the Church of the Holy Innocents at Hoboken.