MECHANICAL ENGINEERING. 143 



lem in prehistoric times, and have never ceased their endeavors; for 

 there is no invention, and never has been imagined an invention more 

 attractive to the mind of man; nor is there any invention the perfection 

 of which would have more interest for mankind or illustrate more splen- 

 didly the triumph of the mind of man over the conditions which hem 

 him in. Yet the century which has seen such marvelous, almost catas- 

 trophic, evolutions in all other fields has seen its end without final 

 success here. 



Yet some important advances have been made. The dirigible bal- 

 loon has become capable of contending wdth moderate winds, and of 

 traversing still air in any direction at moderate speed and for small 

 distances; the balloon itself and its motors are taking definite form and 

 standard proportions, especially in the hands of the military staff of the 

 armies of European nations. Our own army officers have not, so far as 

 knowm, entered upon this task, though having at hand the most royal 

 inventors of the world. Count Zeppelin probably illustrates the furthest 

 advance in this department. 



In aerodromics. Professor Langley has completely developed the 

 fundamental principles of self-sustaining flight, and has revealed the 

 fact that there are far fewer and far less formidable obstacles to be 

 overcome in this direction than had been previously supposed. Hia 

 researches are the classics of this division of applied science, and his 

 experimental investigations of the laws of this science will permanently 

 stand as the first important steps in the development of the rational 

 basis of all future work, and as the foundations of aerodromic science; 

 while his extraordinary work in the practical evolution of the aerodrome 

 — the more wonderful as the work of a scientific man whose vocations, 

 and until recently whose avocations, have been in quite other depart- 

 ments than those of mechanical construction — will always remain 

 famous as the first deliberate and successful attempt to carry into prac- 

 tice principles thus revealed. In the nineteenth century, we may at 

 least claim, these first advances on firm grounds have been effected, and 

 we need not be at all surprised if, in the earlier years of the new cen- 

 tury, complete success, so far as the mechanical engineering of the case 

 is concerned, shall be attained. There is some reason to doubt whether 

 commercial success will follow — not that it is in itself inherently im- 

 possible, but that it is a question whether, in the presence of the com- 

 petition of the more advantageous methods of transportation on solid 

 land and with the buoyant and hardly less effective support of the ocean 

 wave, conveyance of passengers and of merchandise can not always be 

 generally effected vastly more safely and cheaply. Yet that there will 

 be found a place and purpose for aviation, in time of war if not in time 

 of peace, and even probably for profitable employment, we may not 

 doubt. 



