136 SECTIONAL ADDRESSES. 
reliable prime-movers they have in fact become. Let me quote in this 
connection some very just remarks by Mr. Ricardo, who has himself 
done not a little towards securing the admirable results he here describes : 
‘With the advent of this class of engine there has been a marked 
change of attitude as regards both the manufacture and the handling 
of prime-movers. In the past, a prime-mover was regarded as a delicate 
piece of mechanism, luxuriously housed, and served by skilled engineers 
trained to anticipate all its needs and to minister to its ailments. To-day, 
the high-speed internal-combustion engine receives no such special care ; 
more than half the engines produced are tended by people who have 
no idea of how they work, and who consider that their obligations are 
fulfilled so long as they keep one compartment reasonably full of fuel and 
another of lubricating oil; it is for such usage that the engine must be 
designed. A typical example of the modern attitude towards the high- 
speed engine is to be found in the case of the motor-bus. The modern 
bus engine is capable of developing 70 to 80 horse-power and of running 
at piston-speeds exceeding 2,000 feet per minute ; it is placed in the hands 
of a driver who knows nothing about engineering generally, or of his 
engine in particular. Such an engine runs 16 hours daily under very 
arduous conditions and, in the ordinary course of events, it continues 
so to do for six months before it receives any skilled attention. It is 
obvious that to withstand such usage an engine must be reliable.’ 
One may note in passing the remarkably successful efforts which 
have lately been made towards reducing the weight of high-speed engines 
which will burn heavy oil instead of petrol, with the consequent advantage 
(over petrol) of greater efficiency, less weight of fuel, greater safety, and 
smaller running cost. Light engines of this type open up new possibilities 
in the air,® as well as on the road and on the sea. 
This brings me to the last field which must be surveyed in our brief 
review—the field of ocean navigation. And here we find a situation 
which is puzzling, unsettled, and difficult to analyse. For in the selection 
of prime-movets for ocean-going ships, there are sharp differences of 
opinion and of practice ;, there is no sense of finality; there is even— 
so it seems to me—a good deal of fashion and caprice, and of the probability 
of change which one associates with such moods of the mind. I do not 
suggest that superintending engineers are ever capricious or wnreasoning ; 
indeed, if the matter were really left to them I believe it would soon 
settle itself ; but even a layman in marine matters knows that a shipping 
company’s policy in questions of propulsion is sometimes governed 
by other factors than the considered judgment of the superintending 
engineer. 
In our own navy and foreign navies there is a practical monopoly 
on the part of steam except, of course, in submarines. The advent 
of the steam turbine, of oil fuel, of gearing between turbine and propeller 
shafts, of water-tube boilers, of higher pressure, and of superheating— 
all these progressive improvements have only consolidated the position. 
Foreign navies have followed the British lead, and, for surface vessels, 
the only departure from that rule is to be found in a new German cruiser, 
®See a lecture by Mr. D. R. Pye on ‘ Heavy-Oil Aero Engines,’ Journ. Roy. 
Aeronautical Society, April, 1931. 
ne 
