friends, that was always felt by them as an endearing mark of his kindness and familiarity, and prized accordingly, far beyond all the solemn compliments that proceeded from the lips of authority. His voice was deep and powerful; though he commonly spoke in a low and somewhat monotonous tone, which harmonized admirably with the weight and brevity of his observations, and set off to the greatest advantage the pleasant anecdotes which he delivered with the same grave tone, and the same calm smile playing soberly on his lips.

"There was nothing of effort, indeed, or of impatience, any more than of pride or levity, in his demeanor; and there was a finer expression of reposing strength, and mild self-possession in his manner, than we ever recollect to have met with in any other person. He had in his character the utmost abhorrence for all sorts of forwardness, parade, and pretension; and indeed never failed to put all such impostors out of countenance, by the manly plainness and honest intrepidity of his language and deportment. "He was twice married, but has left no issue but one son, associated with him in his business and studies, and two grandchildren by a daughter who predeceased him. He was fellow of the Royal Societies both of London and Edinburgh, and one of the few Englishmen who were elected members of the National Institute of France. All men of learning and of science were his cordial friends; and such was the influence of his mild character, and perfect fairness and liberality, even upon the pretender to these accomplishments, that he lived to disarm even envy itself, and died, we verily believe, without a single enemy."

W

VI

THE MASTER WORKER

E have already pointed out at some length that, in the hands of Watt, the steam engine came at once to be a relatively perfect apparatus, and that only three really important modifications have been applied to it since the day of its great perfecter. These modifications, as already named, are the doing away with the walking beam, the utilization of high pressure steam, and the development of the compound engine. Each of these developments requires a few words of explanation.

The retention of the heavy walking beam for so long a time after the steam engine of Watt had been applied to the various purposes of machinery, illustrates the power of a pre-conceived idea. With the Newcomen engine this beam was an essential, since it was necessary to have a weight to assist in raising the piston. But with the introduction of steam rather than air as the actual power to push the piston, and in particular with the elaboration of the double-chamber cylinder, with steam acting equally on either side of the piston, the necessity for retaining this cumbersome contrivance no longer existed. Yet we find all the engines made by Watt himself, and nearly all those of his contemporaries, continuing to utilize this means of transmitting the

power of the piston. Even the road locomotive, as illustrated by that first wonderful one of Trevithick's and such colliery locomotives as "Puffing Billy" and "Locomotion," utilized the same plan. It was not until almost a generation later that it became clear to the mechanics that in many cases, indeed in most cases, this awkward means of transmitting power was really a needlessly wasteful one, and that with the aid of fly-wheel and crank-shaft the thrust of the piston might be directly applied to the wheel it was destined to turn, quite as well as through the intermediary channel of the additional lever.

The utility of the beam has, indeed, still commended it for certain purposes, notably for the propulsion of side-wheel steamers, such as the familiar American ferryboat. But aside from such exceptional uses, the beam has practically passed out of existence.

There was no new principle involved in effecting this change. It was merely another illustration of the familiar fact that it is difficult to do things simply. As a rule, inventors fumble for a long time with roundabout and complex ways of doing things, before a direct and simple method occurs to them. In other words, the highest development often passes from the complex to the simple, illustrating, as it were, an oscillation in the great law of evolution. So in this case, even so great an inventor as Watt failed to see the utility of doing away with the cumbersome structure which his own invention had made no longer a necessity, but rather a hindrance to the application of the steam engine. However, a new generation, no longer under the thraldom of the ideas of the great

inventor, was enabled to make the change, gradually. but in the end effectively.

HIGH-PRESSURE STEAM

As regards the use of steam under high pressure, somewhat the same remarks apply, so far as concerns the conservatism of mankind, and the influence which a great mind exerts upon its generation. Just why Watt should have conceived an antagonism to the idea of high-pressure steam is not altogether clear. It has been suggested, indeed, that this might have been due to the fact that a predecessor of Watt had invented a highpressure engine which did not use the principle of condensation, but exhausted the steam into open space. As early as 1725, indeed, Leupold in his Theatrum Machinarum, had described such a non-condensing engine, which, had it been made practically useful, would have required a high pressure of steam. Partly through the influence of this work, perhaps, there came to be an association between the words high pressure and non-condensing, so that these terms are considered to be virtually synonymous; and since Watt's great contribution consisted of an application of the idea of condensation, he was perhaps rendered antagonistic to the idea of high pressure, through this psychological suggestion. In any event, the antagonism unquestionably existed in his mind; though it has often enough been pointed out that this seems the more curious since high-pressure steam would so much better have facilitated the application of that other famous idea of Watt, the use of the expansive property of steam.

Curiously enough, however, the influence of Watt led to experiments in high-pressure steam through an indirect channel. The contemporary inventor, Trevithick, in connection with his partner, Bull, had made direct-acting pumping engines with an inverted cylinder, fixed in line with the pump rod, and actually dispensing with the beam. But as these engines used a jet of cold water in the exhaust pipe to condense the steam, Boulton and Watt brought suit successfully for infringement of their patent, and thus prevented Trevithick from experimenting further in that direction. He was obliged, therefore, to turn his attention to a different method, and probably, in part at least, in this way was led to introduce the non-condensing, relatively high-pressure engine. This was used about the year 1800. At the same time somewhat similar experiments were made by Oliver Evans in America.

Both Trevithick and Evans applied their engines to the propulsion of road vehicles; and Trevithick is credited with being the first man who ran a steam locomotive on a track,-a feat which he accomplished as early as the year 1804. We are not here concerned with the details of this accomplishment, which will demand our attention in a later chapter, when we come to discuss the entire subject of locomotive transportation. But it is interesting to recall that the possibilities of the steam engine were thus early realized, even though another generation elapsed before they were finally demonstrated to the satisfaction of the public. It is particularly interesting to note that in his first locomotive engine, Trevithick allowed the steam exhaust [113]

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