■ ENGINEERING. 291 



and contraction of the pipes, the range being more than an inch in a hundred 

 feet. This is provided for by making the end of each section, of about 80 or 100 

 feet, terminate in very flexible diaphragms of thin copper, the diaphragms being 

 supported by stiff iron ribs. 



Among the great enterprises in contemplation, is the interoceanic canal, or 

 the interoceanic railroad for large ships. This is not the occasion for expressing 

 any opinion on any of the competing projects. I will only say that if the world 

 is determined to have a sea level canal, it makes a great mistake in not getting 

 fuller information about the San Bias route. 



Many things that have been done by this generation seemed beforehand far 

 less possible than the successful working of the ship railway proposed by Captain 

 Eads. The difficulties are certainly very great, but we can see how they may be 

 overcome. The real question is, whether taking into account the expense of 

 overcoming those difficulties, the construction and operation of si ch railway will 

 be more economical in the end than the construction and operation of some one 

 of the proposed canals. 



The last year has been one of intense activity, particularly in railroad con- 

 struction. A year or two ago money was so abundant, and, therefore, interest 

 so low, and so many capitalists, great and small, were tired of letting their money 

 lie idle, that new enterprises of many kinds were started, especially new railroads, 

 and enlargements of capacity of those al/eady in use. As the money market has 

 approached its normal condition, some of the new projects have been dropped. 



It is instructive to look back and trace the connection between the progress 

 of railroads and the financial condition of the country. 



•^ %■;>(. ■:^ ■^ -if. 



The railroads opened in the United States^ January i, 1880, aggregated 86,- 

 500 miles in length, being 40 per cent of all the railroad mileage of the world. 

 Last year we had 93,600 miles, and this year we have just about 100,000 miles. 

 But mere length is a very inadequate measure of their magnitude. The terminal 

 mile of some roads has probably cost as much as five hundred miles of some other 

 roads. At one time, and possibly now, the cost per ton taken, on the first two 

 miles of the road from New York to Pittsburg, was more than the cost of carry- 

 ing that ton over the next two hundred miles. The increase in aggregate magni- 

 tude of all the roads may be almost as much in the enlargement without increase 

 in length of the old, as in the extension of the new. We hear in more than one 

 case of thirty miles of additional terminal tracks being laid at one point. 



The diminished plethora of money, and the greater caution now apparent, 

 will, it is to be hoped, moderate the increase of the means of production and 

 transportation, so as to prevent another stagnation. 



The investment in railroad property in the United States is set down at about 

 $5,000,000,000, perhaps about one-eighth of the value of all the property of the 

 country, real and personal. 



When we speak of the extraordinary magnitude of the engineering works of 

 the present day, we do not forget the pyramids, temples, and fortifications of 



