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.  Go.  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.

[Illustration:  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: 

Ft.  In. 
Clear opening between abutments      291 4
Rise of arch                          32 93/4
Width of bridge                       37 43/4
Depth of arched girders                4 7

[Illustration:  BRIDGE OVER THE RIVER ADIGE, AT VERONA.]