J 4 A STATISTICAL ACCOUNT OF THE 



A little out of its order, is mentioned the last unex- 

 ecuted plan, for erecting a wooden bridge, over the' 

 middle ferry, in the year 1767. A subscription for the 

 purpose was circulated, and many respectable citizens 

 agreed to contribute. But this, from various causes, 

 fell through; and all efforts to accomplish the object 

 were suspended for many years. This bridge was 

 contemplated to be of one arch, with stone abutments ; 

 a plan still believed by some of its former advocates, 

 to be practicable and most (Economical. The intended 

 span was to have been 400 feet: height from the 

 water 47 1 -2 feet. 



In theory, it seems reconcilable with principles, that 

 an arch of wood or iron, may be extended to any length 

 of span, \^ ith sufficient elevation. The point of either 

 practicability or discretion, has never been precisely fix- 

 ed. In a modern proposal for a single arch of iron, 

 over the Thames^ in place of old London Bridge^ a project 

 is exhibited for an arch of 600 feet span. All agree 

 in the theory, but practical men shrink at the danger; 

 though there are respectable opinions of intelligent the- 

 orists, in favour of its principles. According to the best 

 opinions of practical men here, (among them Mr. JFest- 

 on and Mr. Palmer^ one of 200 feet begins to be criti- 

 cal and hazardous. The timber arch of Piscataway 

 bridge, erected by Mr. Palmer, spans 244 feet , but he 

 declared he would not again attempt one of similar extent. 

 The most intelligent among those who have gained ex- 

 perience in the late structure, believe, that the span in- 

 tended for the Schuylkill, in the last project, the draft 

 whereof has been often seen by them, was too extended 

 for this fipot; and that it would most probably have fail. 



