4(52 STATE BOARD OF AGRICULTURE. 



was to run it at its introduction, we are aniazod to find such wonderful 

 impi-ovenicnt in so short a period. 



I'roliably since James ^Vatt made his inij)rovenients uj)on the steam 

 cnj^inc. thi'rc has been nothing that lias jxiven so much impetus to 

 the engineering world as the universal ad()i>tion of electrically driven 

 cars as a means for rapid transit. It has opened new fields for the 

 three engineering i)rofessions, civil, mechanical and electrical. 



The civil engineer must l)etter the line consti'uction, making it more 

 substantial, and capable of standing heavier strains. Overhead roads 

 and tunnels liaAe become a necessity in the more thickly populated 

 portions of our large cities. Bridges before unthonglit of, or considered 

 impossible of construction, have been designed. Only a few years ago 

 the Brooklyn bridge was looked upon as a marvelous })iece of engi- 

 neering, but today i)eople regard as almost a matter of course the 

 new North River bridge, which when comi)leted will outclass the former 

 in every particular. The tunnels of our large cities may be looked upon 

 as feats of modern civil engineering to which the demand for rapid 

 transit has given rise. 



The duties of the mechanical engineer lie at the base of all sources 

 of power and the advancement made necessary in the mechanical field 

 by the need of more rapid means for transit has been of much import- 

 ance. There are in general but two main sources of power; first, the 

 conversion of the energy stort^d up in coal, or its products, through the 

 heat engine; and second, water power. There are so far as we know 

 today no material sources of electricity, so we must depend on one 

 of these sources of power to develop it. 



When the dynamo was first put to practical use it had to be run with 

 high velocity. The only engine then in use was a slow-speed one, with 

 the ball governor in no better condition than it was left by James 

 Watt. The water turbines of that time were no better fitted to run at 

 the enormous rate required, consequently elaborate counter-shafting 

 became necessary and much power was lost through transmission. 



The mechanical engineer had serious problems to face. He must have 

 an engine that would run, at what seemed in that day, an almost im- 

 possible speed. It was necessary to devise some better means for gov- 

 erning, and the new engine had to be capable of standing heavier strains 

 than was ever demanded of the old. 



To increase speed necessitated higher pressures, and higher pressures 

 necessitated more eflScient and stronger boilers. 



The mechanical engineer has worked long and diligently and his 

 labors have been fittingly rewarded. The question of speed has been 

 solved and today we find in our best power plants either the dynamos 

 belted directly to the engines or mechanically connected with them. Reg- 

 ulation has been perfected to such a degree that a monstrous engine will 

 respond to the least variation in load. Thermodynamic losses have 

 been gradually reduced, and today we see our steam engine so highly 

 perfected that it is not i>robable that it will be bettered till some 

 genius comes forward and shows to the world the method of direct con- 

 version of the energy of chemical forces into mechanical energy, and 

 when that day shall come, our present engine, of which we are so 



