Scientific Lectures. 195 



of the riveting, of the lateral strength of the beam against gales of 

 wind, of the strength of the stone and brick upon which the girders, 

 <fec., of 8,000 tons were to rest, all of which experiments cost upward 

 of §50,000 ; but they enabled the engineer to lay down his plans with 

 great certainty, saving on the one hand any unnecessary weight of 

 metal in any part of the tube, and on the other from the weakness of 

 some part, which would have lessened the strength and value of the 

 whole structure. Before a blow had been struck upon this work, the 

 engineer had completed his plans so perfectly that he had even marked 

 out the position and size of every rivet in the tubes. Many volumes 

 have been written descriptive of this work, whicli have been translated 

 into the language of every civilized nation. It is true that the engi- 

 neer would not now duplicate such a girder, but a quarter of a century 

 ago it was the boldest engineering work of its kind. 



Great Engesteeking Projects. 



I will close this address with a reference to some of the great 

 engineering works which have been projected in our day. In a 

 recent paper, emanating from a board of distinguished engineers, 

 they remark as follows : " There is danger that under the incentives 

 of these wonderful achievements the engineer may be led either to 

 attempt impossibilities, or what is more likely, to venture too far 

 into an untried field of labor," and they add, "He (the engineer) 

 would fail in his duty, and in a proper comprehension of his mission, 

 if he allowed himself to project plans merely for his own personal 

 eclat or aggrandizement, or if he did not confine himself to the most 

 safe, practicable, and reasonable metliods of accomplishing the results 

 which are demanded of him." These conservative opinions, intended 

 for the cautious capitalist, were doubtless those of a large proportion of 

 the members of that convention, but among the engineers then present 

 were some, who had themselves left the routine rules of the profession 

 and demonstrated the possibility of plans which had previously been 

 questioned. When we use the word " impossible," it as often indi- 

 cates that our knowledge or reasoning faculties are insfifiicient to 

 grasp the subject presented, as that the subject itself is in conflict with 

 the laws of nature. ]^ot very long ago it would have been hazardous 

 to have advocated steam navigation, railway locomotion, or electric 

 telegraj^hy. While Dr. Lardner was lecturing against the possibility 

 of a vessel being able to cross the Atlantic by steam, the Sirius and 

 Great Western steamers were on their first voyage from England to 



