THE GREAT BRIDGE AND ITS LESSONS. 345 



origin of the work, or any complicity with fraud in its execution and 

 completion. It is this consideration which induced me to accept the 

 unexpected invitation of the trustees to speak for the city of New York 

 on the present occasion. When they thus honored me, they did not 

 know that John A. Roebling addressed to me the letter in which he first 

 suggested (and, as far as I am aware, he was the first engineer to sug- 

 gest) the feasibility of a bridge between the two cities, so constructed 

 as to preserve unimpaired the freedom of navigation. This letter, dated 

 June 19, 1857, I caused to be printed in the " Journal of Commerce," 

 where it attracted great attention because it came from an engineer 

 who had already demonstrated, by successfully building suspension 

 bridges over the Schuylkill, the Ohio, and the Niagara Rivers, that he 

 spoke with the voice of experience and authority. This letter was the 

 first step toward the construction of the work, which, however, came 

 about in a manner different from his expectations, and was finally com- 

 pleted on a plan more extensive than he had ventured to describe. It 

 has been charged that the original estimates of cost have been far ex- 

 ceeded by the actual outlay. If this were true, the words of praise 

 which I have uttered for the engineers who designed and executed this 

 work ought rather to have been a sentence of censure and condemna- 

 tion. Hence the invitation, which came to me unsought, seemed rather 

 to be an appeal from the grave for such vindication as it was within 

 my power to make, and which could not come with equal force from 

 any other quarter. 



Engineers are of two kinds the creative and the constructive. 

 The power to conceive great works demands imagination and faith. 

 The creative engineer, like the poet, is born, not made. If to the 

 power to conceive is added the ability to execute, then have we one 

 of those rare geniuses who not only benefit the world but add new 

 glory to humanity. Such men were Michael Angelo, Leonardo da 

 Yinci, Watt, Wedgwood, Brunei, and Stephenson ; and such a man 

 was John A. Roebling. It was his striking peculiarity that, while his 

 conceptions were bold and original, his execution was always exact 

 and within the limits of cost which he assigned to the work of his 

 brain. He had made bridges a study, and had declared in favor of 

 the suspension principle for heavy traffic, when the greatest living au- 

 thorities had condemned it as costly and unsafe. When he undertook 

 to build a suspension-bridge for railway use, he did so in the face of 

 the deliberate judgment of the profession, that success would be im- 

 possible. George Stephenson had condemned the suspension principle 

 and approved the tubular girder for railway traffic. But it was the 

 Nemesis of Stephenson's fate that, when he came out to approve the 

 location of the great tubular bridge at Montreal, he should pass over 

 the Niagara River in a railway-train, on a suspension-bridge, which he 

 had declared to be an impracticable undertaking. 



When Roebling suggested the bridge over the East River, his ideas 



