Stewart. — Address. 5 



can be conferred by heredity in such a case, entered into 

 business on the Clyde. Although the compound engine had 

 been invented and iu mining use in Cornwall at the close of 

 the eighteenth century, it was left for John Elder to see the 

 vast possibilities of the application of the principle to marine 

 work. Previous to his time the steam - pressure used in 

 marine boilers was about 7 lb. per square inch, and the diffi- 

 culty in introducing the compound design lay principally in 

 the deeply rooted prejudice existing against high pressures 

 at sea. In 1853, however, Messrs. Randolph, Elder, and Co. 

 commeuced the innovation entailing the most radical de- 

 parture from former practice. I well remember the opposi- 

 tion set up, alike by owners and the engine-room staff, and I 

 watched with much interest the steady, if not rapid, triumph 

 of high initial pressure and expansion to extreme limits in 

 separate cylinders. John Elder died in 1869, at the early age 

 of forty-three. Had he survived to the present day, what 

 would he have seen as the result of his sound judgment of 

 fifty years ago ? He would have seen marine boilers carrying 

 steam at 2801b. to the inch, and expanding in three or four 

 stages through five cylinders, with piston-speeds of 900 ft. per 

 minute. He would have seen the consumption of fuel at sea 

 reduced from more than 6 lb. per horse-power per hour to less 

 than 1 lb. And, solely as the outcome of these results, he 

 would have seen the Atlantic Ocean virtually a ferry, crossed 

 by more than half a million of passengers last year, and our 

 own colony, for the Panama service of which he built the 

 " Rakaia," served with steam-liners not one of which would 

 have been possible under the old system. And, lastly, he 

 would have seen the cargo-steamer " Inchmarlow " carrying 

 1 ton one sea mile by the combustion of one-third of an ounce 

 of coal, which, taking the price at 15s. per ton, is equivalent 

 to carrying 1 ton 550 miles for Id. But the most startling 

 innovation in the marine engine is undoubtedly the steam- 

 turbine of the Hon. Mr. Parsons. By this means velocities 

 have been reached of forty-three statute miles per hour, with 

 an utter absence of that vibration which, at high speeds, is at 

 once so distressing and destructive. Whether the steam- 

 turbine can be applied to an Atlantic liner remains to be 

 seen. There are several drawbacks inherent to the design, 

 the principal of which is the impossibility of reversing the 

 turbine, so that separate machinery has to be provided for 

 going astern, and which is allowed to run loose when the 

 vessel is going ahead. It is certainly not in its favour that, 

 even in the small vessels in which this turbine has been tried, 

 the power has to be applied through three propeller-shafts, 

 each with three screws, the whole revolving at the enormous 

 velocity of two to three thousand revolutions per minute. 



