And although I do not question but the plan and draught of my engine will be very well and readily understood with many gentlemen, by the description here given; yet it will require a longer time in others to employ their minds and thoughts more intensely about it, especially such as have not been familiar and acquainted with things of this kind; but 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. _London, Sept. 22,_ 1701. A DESCRIPTION OF THE DRAUGHT OF THE ENGINE, FOR RAISING WATER BY FIRE. _a_, _a_, The furnaces. _b_, B, the two fire-places. _c_, the funnel or chimney. _d_, the small boiler. _e_, the pipe and cock of it. _f_, the screw that covers and confines its force. _g_, a small cock, a pipe going within eight inches of its bottom. _h_, A larger pipe going the same depth. _i_, a clack on the top of the said pipe. _k_, a pipe going from the box of the said clack or valve, into the great boiler, about an inch into it. _l_, the great boiler. _m_, the screw with the regulator. _n_, a small cock and pipe going half way down the great boiler. _o_, O, steam-pipes, one end of each screw to the regulator, and the other ends to the receivers. _p_, P, the vessels called receivers. _q_, q, the screws which bring on the pipes and clacks in the front of the engine. _r_, _r_, R, R, valves or clack of brass, with screws to open and come at them upon occasion. _s_, the force-pipe. _t_, the sucking-pipe. _v_, a square frame of wood, with holes round its bottom in the water. _x_, a cistern with a buoy-cock coming from the force-pipe. _y_, a cock and pipe coming from the bottom of the said cistern. _z_, the handle of the regulator. CHAPTER FIRST. MANNER OF WORKING THE ENGINE. * * * * * THE MANNER OF WORKING THE ENGINE.