Thomas Savery

"Should the engine, to the apprehension of some, seem intricate and difficult to be worked, after all the description I have given of it in this book, yet I can, and do assure them, that the attending and working the engine is so far from being so, that it is familiar and easy to be learned by those of the meanest capacity, in a very little time; insomuch that I have boys of thirteen or fourteen years of age, who now attend and work it to perfection, and were taught to do it in a few days; and I have known some learn to work the engine in half an hour. We have a proverb, that interest never lies; and I am assured that you gentlemen of the mines and collieries, when you have once made this engine familiar in your works, and to yourselves and servants; not only the profit, but abundance of other advantages and conveniences which you will find to attend your works in the use thereof, will create in you a favourable opinion of the labours of Your real Friend and humble Servant, THOMAS SAVERY"

"I only just hint this to show what use this engine may be put to in working of mills, especially where coals are cheap. I have only this to urge, that water in its fall from any determinate height, has simply a force answerable and equal to the force that raises it."

"Amongst the several Engines which have been contriv'd for the raising of Water for the Supply of Houses and Gardens, none has been more justly surprising, than that for the raising of Water by Fire; the particular Contrivance and sole Invention of a Gentleman, with whom I had the Honour long since to be well acquainted; I mean, the ingenious Captain Savery, sometime since deceased, but then a most noted engineer, and one of the Commissioners of the Sick and Wounded. ...It was a considerable Time before this curious Person, who has been so great an Honour to his Country, could, (as he himself tells us) bring this his Design to Perfection, on account of the Aukwardness of the Workmen, who were necessarily to be imploy'd in the Affair; but at last he conquer'd all Difficulties, and procur'd a Recommendation of it from the Royal Society, in Transac. No. 252. and soon after, a Patent from the Crown, for the sole making this Engine; And I have heard him say my self, that the very first Time he play'd it, it was in a Potter's House at Lambeth, where, tho' it was a small Engine, yet it forc'd its Way thro' the Roof, and struck up the Tiles in a Manner that Surpris'd all the Spectators."

"What I say here is not to give room for believing, that Mr. Savery, who has since published this invention at London, is not actually the inventor. I do not doubt that the same thought may have occurred to him, as well as to others, without having learnt it elsewhere."

"I soon relinquished the idea of constructing an engine upon its principle, from being sensible it would be liable to some of the objections against Savery's engine, viz., the danger of bursting the boiler, and the difficulty of making the joints tight, and also that a great part of the power of the steam would be lost, because no vacuum was formed to assist the descent of the piston. I, however, described this engine in the fourth article of the specification of my patent of 1769; and again in the specification of another patent in the year 1784, together with a mode of applying it to the moving of wheel-carriages."

"In June, 1699, Captain Savery exhibited a model of his engine before the Royal Society, and the experiments he made with it succeeded to their satisfaction. It consisted of a furnace and boiler B: from the latter, two pipes, provided with cocks C, proceeded to two steam vessels S, which had branch pipes from a descending main D, and also to a rising main pipe A: each pair of branch pipes had check] valves a, b to prevent the descent of the water raised by the condensation or by the force of steam. Only one vessel, S, is shown, the other being immediately behind it. One of the steam vessels being filled with steam, condensation was produced by projecting cold water, from a small cistern E, against the vessel; and into the partial vacuum made by that means, the water, by the pressure of the atmosphere, was forced up the descending main D, from a depth of about twenty feet; and on the steam being let into the vessels again, the valve b closed, and prevented the descent of the water, while the steam having acquired force in the boiler, its pressure caused the water to raise the valve a, and ascend to a height proportional to the excess of the elastic force of the steam above the pressure of the air."