128 SECTIONAL ADDRESSES. 
Steam is neither dead nor dying. On the contrary, its use has immensely 
developed both on land and sea. To-day, it is a much more efficient 
medium than it was for the conversion of heat into work, and you find it 
actuating engines of vastly greater individual and aggregate power 
than any that were even imagined when Bramwell spoke. But alongside 
of that we have wonderful achievements on the part of the internal- 
combustion engine which go far to justify the enthusiasm that stirred him 
fifty years ago. 
Looking back now, one is amazed at the boldness of his prophetic 
outlook. It was more than bold; it was almost foolhardy. Remember 
that he had nothing to go by except the performance of the gas-engine, 
and that only in very small powers. Gas, whether the ordinary illuminat- 
ing gas distilled from coal, or the cheaper product of the Dowson process, 
was the only fuel then in practical use for internal combustion. The 
oil engine in its various forms, the petrol engine, the Diesel engine— 
these were still to come. 
The gas-engine itself did not develop so fast as those who had faith 
init might have hoped. Sir Dugald Clerk, whose invention of the two-stroke 
cycle was followed up by many other important services to internal 
combustion, and who has become its historian, tells us that even in 1898 
the largest.gas-engines then built indicated 220 horse-power. By that time, 
however, B. H. Thwaite had demonstrated that the so-called waste gases 
of the blast furnace were a suitable fuel, and this led makers, especially 
on the Continent, to take up the design of large gas-engines in forms 
which for some years had a conspicuous vogue. There were examples 
in which as much as 2,000 horse-power was developed in a single cylinder 
working on the Clerk cycle, and a four-cylinder engine was built to 
indicate 8,000 horse-power. Such engines were notable for their great 
bulk and weight. They were also, for the most part, costly failures. 
The big cylinders, cylinder-heads and pistons were apt to crack. The 
difficulty of controlling the temperature of the metal and escaping 
effects of unequal expansion stopped the construction of gas-engines 
with large cylinders. Moreover, apart from that check it soon became 
clear that the chief advance of internal combustion was to take place on 
different lines, namely by having oil serve as the internal fuel. Gas 
still plays a useful part, but quite definitely a minor part. The builders 
of gas-engines have wisely sought security by restricting the dimensions 
of their cylinders, and confidence in their wares is now restored. Their 
products have a well-established and considerable market. But nowadays 
when we would treat of what internal combustion has accomplished, 
and of its future, we turn not to gas-engines but to engines which use liquid _ 
fuel. We think instinctively in terms not of gas but of oil, using that 
word to include not only the ‘ heavy’ petroleum of the Diesel motor, but 
the more volatile constituents with a lower flash-point, which in this 
country go by the name of petrol. 
The success of the Otto gas-engine led makers to design engines 
operating in much the same way but using for fuel a spray of oil instead of 
gas. Such engines found a place where gas was not available, as in the 
driving of agricultural machinery. For the most part their fuel was the 
safe and familiar oil of the paraffin lamp. Like the gas-engine, they were 
