286 Improvement in the Construction of Bridges, §c. 
“Tf the bridge is of greater extent than can be included in one 
span, it is simply rested on a thin pier, in the manner shown in 
the elevation, without any other support. A covering of light 
boarding, extending from the level of the road-way to the bottom 
of the ribs, is spiked on the outside of the lattice-work to preserve 
the timber. 
“ The largest lattice-bridge which I met with, was constructed 
by Mr. Robinson, on the Philadelphia and Reading Railroad. 
It measures 1,100 feet in length. The lattice-frames, of which 
it is formed, extend throughout the whole distance, between the 
two abutments, without a break, and are supported on ten stone 
piers, in the manner shown in the plates. ° 
‘“ On the New York and Harlem Railway, there is a lattice- 
bridge 736 feet in length, supported in the same manner, on four 
stone piers.” 
ince the above, there have been others finished, of much greater 
extent and goodness, both under the direction of Moncure Robin- 
son, Esq. and others. That at Richmond, Va., is so remarkable 
for its magnitude and grandeur of effect, from the very bold and 
rich landscape of that fine city, that its description may well be 
here introduced, for it will convey both practical information and 
rational entertainment.* 
The Railroad Bridge across James River. 
What is there yet to be done upon the face of the earth, that 
cannot be effected by the powers of the human mind, connected 
with the ingenuity of the human hand? The great elementary 
principles of nature have long ago been mastered by the skill of 
“ies Ribs eo 
* The following description of a bridge, constructed on the improvement * 
Ithiel Town, as patented in 1835, it is fully believed will serve to show, not st 
the confidence of one of the most eminent and experienced engineers of the Unt 
ted States, in the superior durability, economy, and strength of principle, 
improved by Mr. Town, but also the confidence which the public now fee 
mode of construction, from this and many other railroad bridges now in use OF 
; e 
one at Circleville, Ohio, &c. Reference to Mr. Town's advertisement 7 the 
- National Intelligencer, of August 5th, 11th, &c., and in the New York Weekly 
Express, of the 4th of August, 1839, for terms and other particulars.—VYew Haves 
Daily Herald, September ,1838. ; 
