REPORT 



Of the committee of Arts and Sciences of the American 

 Institute, on the model of a wooden bridge, submitted 

 by Lowman Gay, of Chili, Monroe county, N. Y. 



The committee, after an examination of the model and an investi- 

 gation of the principles on which its strength is founded, are of opi- 

 nion that Mr. Gay has reduced the method of spanning large openings 

 by frames of timber, so combined as to remove all lateral thrust, to 

 the utmost simplicity of %vhich it is capable. In the use of this plan 

 therefore, all costly and heavy abutments are rendered unnecessary, 

 while the combination of pieces in the frame presents fewer parts, 

 and those more skilfully adapted to each other and to the .strain to 

 which they are subjected, than in any other plan which has come to 

 their knowledge. The mode of combination of the parts composed 

 of wood, aided by a series of iron rods, appears to render the struc- 

 ture incapable of flexure, until its limit of fracture is approached, 

 while, in consequence of the lightness of the structure, that limit will, 

 in large spans, when the weight of the arch itself is the most impor- 

 tant disturbing agent, be removed far beyond that of other analogous 

 plans. They are, in consequence, of opinion, that the frame exhibi- 

 ted by Mr. Gay will be capable of spanning with safety, openings of 

 larger extent than any other with which they are acquainted, and of 

 spanning openings of a given extent, at a less cost of material and 

 workmanship. 



By order of the committee, 



JAS. RENWICK, Chairman. 

 American Institute ^ June 10th, 1846. 



