22 PRESIDENTFAL ADDRESS SECTION A. 



to develop one indicated horse-power in the engine. A good 

 suction gas engine and generator working with best Welsh anthra- 

 cite will equal and improve upon this performance. At the 

 same time gas engines are working on town gas — obviating the 

 complication, space and mess involved in a boiler plant, or gas 

 may be produced in a generator from almost any fuel or refuse 

 which can be made to liurn. Or, again, the waste gases of the 

 blast furnace may be used. Engines using town gas are an 

 obvious convenience to users of small powers in urban areas 

 where gas mains are installed. The engine working with its own 

 gas generator, more especially the suction gas engine, has made 

 power available to thousands of users who could otherwise only 

 obtain power at a high, or even prohibitive, cost. Many power 

 users in South Africa have scrapped a steam j^lant, installed a 

 larger suction gas plant, and have paid for the latter out of 

 one, or. at the most, two years' saving in running costs. 



The enormous engines installed at up-to-date iron or steel 

 works, and working on waste bia.sl furnace gas. save these works 

 great sums of money annually, which were formerly spent on 

 coal. To give an example of one of these large installations, at 

 the v.'crks of the Indiana Steel Company, there are in one power 

 house 1/ sets of large Nurenberg type engines, each developing 

 2,500 kilowatts, or 3,000 B.H.P. ; 51,000 B.H.P. in all. Both on 

 the continent of Europe and in the United States there are many 

 large blast furnace gas engines developing over 5,000 B.H.P. 

 for each unit. 



Coming to the oil engines, these equal the gas engines for 

 efficiency, but their great merit lies in the convenient form of 

 fuel. A pint of oil per B H P. bour represents but little I)ulk, 

 and oil engines are consequently larger in use as portable machines 

 or tractors for agricultural and other purposes. 



All the smaller gas and oil engines are very easy to manage, 

 and require no reg^ular expert attention, and can all be started 

 up from cold within a few minutes — the least characteristic is of 

 enormous advantage to the small ijower user The small high- 

 speed engine working on petrol or alcohol falls into a separate 

 class. The thermal efficiency of these engines falls considerably 

 short of that obtained in gas engines, and rarely exceeds 25 per 

 cent, when working at fairly high speeds, but the value of these 

 engines lies in other directions. 



The extraordinarily small weight of these engines per horse 

 power, the high speed of rotation, ease and speed with which 

 they can be started, the small bulk of the fuel supply and its 

 convenience, have endowed these motors with an importance 

 hardly realised by most people. Modern automobilism and 

 aviation, and all that these terms stand for, are the direct residt 

 of the development of this type of engine by Daimler. Daimler 

 produced the first motor bicycle and the first successful motor- 

 car. Besides, Daimler, Benz deserves a considerable amount of 

 credit as a pioneer in the production of an internal combustion 



