Robert M. Vogel 



THE ENGINEERING CONTRIBUTIONS 

 OF WENDEL BOLLMAN 



The development of structural engineering has .//nays been 

 as dependent upon the availability of materials as upon the 

 expansion of theoretical concepts. Perhaps the greatest .angle 

 step in the history of civil engine cy nig was the introduction of 

 iron its a primary structural material in the 19th century; it 

 quickly released the bridge and the building from the confines of a 

 technolog i based upon the limited strength of masonry and wood. 



Wendel Bollman, self-taught Baltimore civil engineer, was 

 the first to evolve a system of bridging in iron to be consistently 

 used on an American railroad, becoming one of the pioneers who 

 ushered in the modern period of structural engineering. 



The Author: Robert M. Vogel is curator of civil engi- 

 neering in the Smithsonian Institution's Museum of History 

 and Technology. 



Wi Mil i in ii i m w s name survives toda) sold) in 

 association with tin- Bollman truss, and even in 

 this respect is known only to a lew older ci\ il .mil rail- 

 road engineers. The Bollman s\ stem ol trussing, along 

 with those of Whipple and Fink, ma) In- said to have 

 introduced the greal age of the metal bridge, and 

 thus, directly, the modern period ol civil engineering, 

 (tollman's bridge truss, ol which the first example 

 was built in L850, has the ver) significant distinction 

 of being the fust bridging system in the world employ- 

 ing iron in .ill of its principal structural members 

 that was used consistently, on a railroad. 



The importance of the transition from wood to 

 iron .1- a structural and bridge building material is 

 generally recognized, but it ma) he well to mention 

 certain aspects of this change. 



The tradition of masonr) bridge construction never 

 attained the great strength in this country which it 

 held in Europe, despite a number of notable excep- 

 tions. There were several reasons ior this. From 

 the \ er\ beginning of colonization, capital was 

 a condition that prevailed until well into the 19th 

 century and which prohibited the use of ma 



el the extremely high costs of labor and 

 transport. An even more important economic con- 

 sideration was die rapidit) with which it was i 

 s.n\ to extend thi don of railways during 



then pioneer years. Unlike the earl) English and 

 European railways, which invariabl) traversed 

 of dense population and industrial ai id were 



thus assured of a significant financial return 

 from the moment that the first rail was down, the 



PAPER 36: ENGINEERING CONTRIBUTIONS OF WENDEL BOLLMAN 



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