The following text may have been generated by Optical Character Recognition, with varying degrees of accuracy. Reader beware!

Nath tes > Se a se are ae ther advanced today than most pro- posed radical improvements 'because the ground has been cleared of the real obstructions by experiment .and development in stationary work, There are no real difficulties in the way, though doubtless many modi- fications in detail, and it only awaits initiative, which with an opportunity of cutting fuel consumption in half and at the same time increasing earn- ing capacity, will not be long delayed. THE GAS ENGINE AND PRO- DUCER PLANT.* BY E. SHACKLETON. The question of the gas engine and producer plant, and its application to marine propulsion, is one that has received a large amount of attention and interest from internal combustion engineers, marine engine builders and shipbuilders, some of the latter who, notwithstanding the fact that the gas engine and the gas plant is the prime mover in their own works, seem to be exceedingly chary of giving a trial to the gas engine in the boats they build or engine. It is natural that, after their intimate acquaintance with the steam engine and its traditions, which in many cases dates from over half a century back, they should be very reluctant to adopt-a new type of prime mover, which but. a few years ago was regarded as only suit- able for operating light printing ma- chinery, where power was required not exceeding 10 horsepower. The greatest of poets, Shakespeare, may perchance voice their sentiments where he says, "'Tis better to bear present ills than face others we know not of.' The natural opposition of the steam engine builder to anything in the nature of a gas engine was up to a few years ago, very actte, and today, in many cases, is still ex- istent. Still, the economic laws must eventually prevail, and, by reason of severe competition, shipowners will be driven, in the near future, to ask from the builders a cheaper running type of boat as far as fuel consump- _tion is concerned, particularly in the matter of the cargo type, 4,000 to 5,000 tons gross. The present steam type of engine employed is no doubt very economical as far as steam goes, with a consumption, under very favor- able circumstances, of slightly over 1 pound per indicated horsepower per hour. The more common range of consumption, however, is in the lo- cality of 134 to 2 pounds per indicated *From a paper read before the British Engi- neering Society. THe Marine REVIEW horsepower per hour. Even if "super- heat" were employed, with the attend- ant wear and tear, it is questionable whether a consumption of 1 pound per indicated horsepower per hour could be maintained. The chief ob- jections to. a gas engine and plant from the marine engineer's point of view, are-- Their inability to reverse. bility, pre-ignitions and _ back-fires, difficulty in starting, accumulations of dirt and carbon in cylinders and pis- tons, poisonous gas from leakage of gas plant. To these objections we would say in regard to: Reversing difficulty--This dealt with in detail later on. Unreliability--There are gas. en- gines at work, and which have been will be at work for the past six years, with periods of from 3 to 6 months, night and day without stopping. Pre-ignitions and __ back-fires.--In well designed gas engines, such as those referred to in this paper, under all normal conditions these troubles are very rare. Starting--The use of compressed air for this purpose has now made the starting as easy as that of the steam engine. Accumulations of dirt and carbon, as a rule, may be traced to an inferior lubricant, or: to excessive lubrication, an item that by a little intelligence on the part of the engineer in charge may soon be rectified. If not from this source, the plant, particularly the scrubbers, requires probably look- ing at, as, under the usual working conditions, a fairly clean gas is de- livered to the engines. - Leakage of Poisonous Gases.--Acci- dents which have occurred under this heading are largely due to the neg- lect of common precaution, and are extremely rare. The danger arising from the escape of poisonous gas (carbonic oxide) is more likely to oc- cur in starting producer plants which work under pressure, and even during the running of such systems should there be any leakage in the plant. In the case of suction plants, which are operated by suction from the en- gine, the period of danger from the escape of poisonous gases 1s limited to the 10 or 15 minutes during which the generator is raised to the neces- sary temperature by the fan. On shipboard a simple system of ventilat- ing fans would reduce any risk to a minimum. 'Wear and Tear and Upkeep.--This is certainly an important item, but as far as the most up-to-date experience Unrelia- 25 ' is concerned, the labor and cost have . been found to be practically little, if any, more than with steam, The gas engine and plant appear to be more directly suited to marine re-_ quirements than the large oil engine, notwithstanding the extra inducement which the latter offers as being self- contained. It is, however, very ques- tionable at the present moment wheth- er the problem of dealing with every description of crude oil, as a fuel in an oil engine has been definitely solved, and even in such event, it is very doubtful if there is any real ad- vantage over the producer plant in power cost. It must also be borne in mind that the most suitable type of engine for operation with crude oil is somewhat complicated and expen- sive to build. In the scheme pro- posed, the writer would like to em- phasize the fact that he has an indi- vidual axe to grind for any particular type of plant, engine, dynamo, or oth- er accessory, and that while he has of necessity selected certain types as particularly suited for the scheme of marine propulsion brought before you, no reflection is intended by non- -- reference to other plants, engines, etc., of high merit. Specialization is ex- tremely necessary to the ultimate suc- cess of the gas boat, and only by such blending of a combination of ship- builders, marine engine builders, gas engine and plant makers, and electri- cal engineers, each bringing their varied experience to bear in construc- tion of the boat and her engines, could the desired results be obtained. After going at length into the de- tails of the forms of gas engines on the market the writer went on to state that a well designed steamer fitted with gas could show a profit of £1,000 over and above the steamer per voyage, irrespective of less labor costs, coaling time saved, cargo dis- charging fuel economy. Over and above this profit it is probably that from £200 to £250 would be saved in minor charges, which could be writ- ten off against the extra cost of con- struction of the boat. In conclusion it may be said tha the moderate power gas boat must. take its place in the marine world at an early date, and the object of this paper is to attract the attention of owners and engineers to the subject with a view to elicit information and provoke discussion. Much misgiving seems to possess the mind of the average marine en- gineer regarding the reliability of the gas.engine, which they regard as a delicate machine, and not to be com- &