The next great improvement of Watt, in addition to the condenser, is the air-pump, the use and absolute necessity for which you will understand when I explain its action.  Watt first used it for his atmospheric engine.  The piston of this engine was kept tight by a flow of oil and water on the top, which tended to make the whole a troublesome and bad-working machine.  The cold atmosphere, as the piston went down, of course followed it and cooled the cylinder.  On the piston again rising, some steam would of course be condensed and cause waste.  If the engine-room could be kept at the heat of boiling water, this would not have been the case, but the engineman who could live in this heat would also require to be invented, and so this had to be given up.  Watt’s next and most important step was the one which brings us to talk of the steam-engine as it now is in the present day.  This important step was the idea, of making the steam draw down the piston, as well as help to drive it up; in the first engines it was raised by the beam, and steam used only to cause a vacuum, so as to let the air drive it down.  All before this had been merely steps in advance, like those of children, who must walk before they can run; so was it with the steam-engine.  It was uphill work for many years, and the top of the hill cannot be said to have been readied till Watt worked out this grand idea.  The first engine could only be called atmospheric; now it was destined to become in reality a steam-engine.  Time would fail were I to attempt to go into any details of all the experiments through which Watt toiled to bring his ideas to perfection—­enough to say that he did so; and I trust you will be able, through the description I will endeavour to give, to understand how well his labour was bestowed, and how beautiful the result has proved for the benefit of the world at large.  In 1773, Watt removed to Soho, near Birmingham, where a part of the works was allotted to him to erect the machinery necessary to carry out his inventions on a grand scale.

We must now proceed to some of the useful points of the engine, all I have before mentioned simply relating to the inventors and improvers; but having brought it so far, I may now, I think, proceed further.  The first use of the steam-engine was simply to raise water from mines, and for long it was thought it could be used for nothing else; so much so, that it was at one time used to raise water to turn wheels and thus produce motion.  One of its first uses after it became a really useful machine was to propel ships, though many a weary hour was spent to bring it to this point.  There is a very pretty monument on the Clyde, dedicated to Mr. Bell, who I believe was the first person who successfully brought steamers to work on its waters.  The first who used steam for ships was Mr. James Taylor, in conjunction with Mr. Miller of Dalswinton.  The danger of the fire-ship took such hold on people’s minds that it was with great toil and difficulty they were persuaded