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In Great Britain the position is more complex, but if the tonnage represented by the large steam vessels, such as the new Cunarder and the MoNarRcH or BERMUDA be subtracted the weight of oil engine and steam driven vessels is about equal, and observing that we are dealing with a purely coal producing country the oil engine appears to en- joy a privileged position, but as many of the ships are for foreign owners or intended for trading in parts of the world where oil is plentiful and coal is dear, the mere statement of figures gives absolutely no indication of the trend of thought of the British ship- owner. In France and Germany the position is somewhat similar. In America and particularly on the West coast, the low price of boiler oil has, in recent years, exercised an im- portant influence on the situation and steam is now favored for all but the most moderate powers. When the in- creased cost of the refined oil required by the oil engine and its heavier lubri- cating oil consumption are taken into account, there is no advantage one way or the other, in which case and for reasons too obvious to mention the established steam plant must win. In support of this it is only neces- sary to refer to the perfectly success- ful three-year-old quadruple screw mo- tor ship BerRMupA and her recently launched steam sister ship MONARCH OF BERMUDA, where fuel oil costs was the only determining factor in the change over in the type of machinery. As regards the combined weight of ma- chinery and fuel for a radius of action of about 5000 miles the balance is at present in favor of the oil engine, but - according to the relative advances in efficiency of the two types this cannot be maintained for very long. High Power Diesel Installations HIS, does not take into account the probable adoption of fabri- cated framing for oil engines to which ‘we will now refer. The effect of the appearance of the German pocket bat- tleship DEUTSCHLAND with her 50,000 brake horsepower oil engines must be considered as having an important bearing on the future of the large mer- cantile motorship, but the difference between the two services have to be taken into account. Bearing in mind that Germany was the chief breeding ground of the oil engine, some allow- ance should be made if a pardonable amount of preference has been shown. It should, however, be noted that but for the intervention of the Great war all German battleships from about 1917 onward would have been propelled by oil engines. In 1915 a 12,000 brake horsepower battleship unit had been completed but was never put to sea Since obviously it would have been madness to carry out such an impor- tant experiment during a _ national ‘emergency. It was destroyed under the terms of the armistice but served as a most vital step in the development of the present type of machinery. Driven legislation to get the maxi- mum fighting qualities out of a given weight, the oil engine was deliberately selected for this particular ship and after full consideration of all alterna- tive types, a choice that would be natural even if all other things were equal. Attack and defense are the only objects for which a warship is made and the propelling machinery is looked upon as a necessary evil and any Saving in weight can be put into guns and armament. It was therefore a great compliment to the oil engine to be selected as the lightest and most ricated structures, because electric welding was practically unknown at that date as a commercial process. An experimental gas engine was actually fitted into an old British gunboat called the RATTLER, but was only mod- erately successful chiefly on account of gas producer and what might be called teething troubles. A riveted structure deflects about twice as much as a solid one, and as rigidity is the essence of good oil en- gine design, there should be a future for the solid welded framing, particu- larly in view of the claim that it is not Motorship Asturias, Royal Mail. Of 22,071 Gross Tons. Built by Harland & Wolff in 1925. First of the Big Motorships Introducing the Stocky Funnel suitable type of power plant. The German admiralty is fully aware of all the advantages of high pressure steam and it is unlikely that it would make the choice merely to glorify the name of Diesel. Radius of action has no _ doubt played an important part in the con- ception of this warship for reasons that do not apply to passenger ships. At reduced powers the oil engine is much more efficient than the steam en- gine and as a warship is very seldom called on to develop more than 25 to 50 per cent of its power, which is all that is necessary for cruising speeds, its radius of action is greatly in- creased. In an emergency full power can be instantly switched on, which is a valuable asset for a fighting ship and a condition that can only be fulfilled by the oil engine. These good points are of little or no moment in the case of large passenger vessels which are, as a rule, able to carry sufficient fuel for the round trip and must always make the voyage from port to port at full power, so that this isolated vic- tory for the large oil engine cannot be taken as a general trend: of thought. The superiority in weight was achieved by making the framing of welded steel plate, but originality can- not be claimed for this practice. About 1910 several Capitaine gas engines were puilt on the Clyde having riveted fab- MARINE REVIEwW—September, 1931 much dearer than cast framing. This claim may be substantiated where weight cutting has previously been done by using troublesome cast steel but in any case cost is of no moment where warships are concerned. It might even compete with cast iron framing for commercial purposes, pro- viding the quantity is such that drop forgings could be used for bearing seat- ings and other such parts, since found- ry wasters would be eliminated and through bolts rendered unnecessary. This would for a time at least, send the large oil engine for mercantile practice ahead of steam plant. The other great saving in weight that made this wonderful ship possi- ble was effected by electrically welding the hull. Here again there is nothing novel since Britain produced such a ship nearly ten years ago, but trade union rules made the cost so high that the experiment was not repeated. This reference is to the rivetless motor ship FuLLAGAR, built by Cammell Laird & Co. at Birkenhead. The great tough- ness of the construction is demon- strated by the rough usage it has re- ceived. On one occasion part of the bottom was lifted about nine inches without leaking a drop of water, and on another, the bows were so badly buckled that a riveted ship would have become a total loss. 29