United States.

To all to whom these Presents shall come, Greeting. Whereas, John Bailey, of Boston, in the State of Massachusetts, hath presented a petition to the Secretary of State, the Secretary for the Department of War, and the Attorney-General of the United States, alledging and suggesting that he hath invented the following useful Machine, not before known or used, that is to say: A Steam Jack, consisting of a boiler, three wheels, and two wallowers; the steam which issues from boiling water in the said boiler gives motion to one of those wheels by striking on buckets on its circumference; on the outer end of the axle of the wheel is a wallower, the rounds of which fall into the teeth of a second wheel; on the axle of this second wheel is another wallower, the rounds of which fall into the teeth of a third wheel; on the axle of which third wheel is a spit: and praying that a patent may be granted therefor: and, whereas, the said invention hath been deemed sufficiently useful and important: These are, therefore, in pursuance of the Act, intitled an Act to promote the progress of useful arts, to grant the said John Bailey, his heirs, administrators, or assigns, for the term of fourteen years, the sole and exclusive right and liberty of constructing, using, and vending to others to be used, the said invention so far as he the said John Bailey was the inventor, according to the allegations and suggestions of the said petition. In Testimony whereof I have caused these Letters to be made patent, and the Seal of the United States to be hereunto affixed. Given under my hand, at the City of Philadelphia, this twenty-third day of February, in the year of our Lord one thousand seven hundred and ninety-two, and of the Independence of the United States of America the Sixteenth. G^o. WASHINGTON.

By the President,

TH. JEFFERSON.

CITY OF PHILADELPHIA, February 23, 1792.

I do hereby certify that the foregoing Letters-patent were delivered to me in pursuance of the Act intitled an Act to promote the progress of useful arts: that I have examined the same, and find them conformable to the said Act.

EDM. RANDOLPH,

Attorney-General of the U.S.

[SEAL.]

BRIDGE AT VERONA.

BRIDGE OVER THE RIVER ADIGE, AT VERONA.

The iron bridge which spans the Adige at Verona, of which we publish illustrations, has been recently completed to replace an old masonry bridge built in the fourteenth century, and which was destroyed by the celebrated flood of 1882. In designing the new work two leading conditions had to be fulfilled, namely, that there should be a single opening of 291 ft. between abutments, and that this width should be left quite unobstructed, for the river is subject to floods, which are frequent, and very violent and sudden. For this latter reason an ordinary form of arch, with the roadway above it, was inadmissible, since the waterway would be seriously obstructed; the special form illustrated was, therefore, carried into execution. The bridge, as will be seen from Figs. 1, 2, 3, and 7, consists of two main arched girders, with two vertical sides in lattice work; these arches spring below the level of the roadway and rise to a considerable height above it, in the center. The horizontal girders carrying the roadway, are connected to the arches by verticals of the form and section shown in the drawings. The longitudinal girders are of double trellis, as will be seen by reference to Figs. 1, 12, and 16. The following are the principal dimensions of the bridge:

The arched girders are connected together, in the central portion, by a system of diagonal bracing, as is shown on Figs. 2 and 7. The carriage road on the platform consists of buckled plates resting on transverse girders spaced 6 ft. 6 in. apart, and covered with road metal, and for the sidewalks checkered plates are used. The ironwork in the bridge weighs 400 tons, and cost 8,400 l.; the abutments cost 3,600l., making the total outlay on the structure 12,000l. The bridge was tested by a uniformly distributed load of 82 lb. per sq. ft., and under this stress the arched girders deflected 1.06 in. The horizontal and vertical oscillation of the bridge, which were carefully observed and graphically recorded by special instruments, were very slight. The engineer of the work was Mr. G.B. Biadego, of Genoa.—Engineering.

BRIDGE OVER THE RIVER ADIGE, AT VERONA.

PUMPING MACHINERY.^[1]

By E.D. LEAVITT, JR., Cambridgeport, Mass.

MINE PUMPING MACHINERY.

One of the earliest steam engines, of any size, introduced into America, was erected about the year 1763, at the Schuylkill copper mine, situated upon the Passaic River, in New Jersey. All its principal parts were imported from England; and a Mr. Hornblower (the son, it is believed, of the well known engineer of that name) came to this country for the purpose of putting up and running this engine.

At the time when the manufacture of the engines for the Philadelphia Water Works was commenced, and as late as the year 1803, we find five engines, in addition to the one above mentioned, noticed as being used in this country: two at the Philadelphia WaterWorks; one just about being started at the Manhattan Water Works, New York; one in Boston; and one in Roosevelt's sawmill, New York; also a small one used by Oliver Evans to grind plaster of Paris, in Philadelphia. Thus, at the period spoken of, out of seven steam engines known to be in America, four were pumping engines.

In the coal regions of Pennsylvania, a simple, high pressure, single acting Bull engine has been extensively adopted; the dimensions usually run from 36 inches to 80 inches in diameter, and a very common stroke is 10 feet. At the Empire shaft, in the Schuylkill coal region, there is a very fine pair of these engines, with 80 inch cylinders, working 24 inch pumps. The stroke of both steam pistons and pumps is 10 feet. These Bull engines are placed either vertically or on an incline, as is most convenient for the workings. The water valves are made either double, triple, or four beat, according as the pumps are large or small; and the beats are usually flat, and faced with leather. Many flap-valves are also in use. These are frequently arranged on conical seats, and work very well.

The Bull engines, from their strength and simplicity, give very little trouble, working year after year with astonishing freedom from accident and slight cost of repair. No attempt is made to economize fuel, which consists mainly of culm, which would otherwise be wasted. Of late, direct acting steam pumps placed under ground have found much favor with mine operators, on account of their portability and small first cost. They usually range in size from 8 inch steam and 5 inch water cylinders by 12 inch stroke to 80 inch stream and 14 inch water cylinders by 36 inch stroke.