“A forcer is a plug of wood exactly turned and leathered about; the end that goeth into the barrel, is semicircularly concave; p. 57. _Forces_ may be made to move either horizontally or perpendicularly, according unto the convenience of the work, or the invention of the artist and engineer; p. 59. (Describing ‘the water mill or engine near the north end of London Bridge.’) These two barrels must be bound fast unto two posts of the frame, with two strong iron bands, as T T; unto each of these must be fitted a _force_ well leathered, and in the tops of the _forces_ must be set two pieces of wood.” Then again, at page 66:--“K K, L L, the barrels of the _forces_, which force the water;” p. 67. “E, a barrel of brass or wood fastened in the well, K, a _force_ fitted into it.” Again, “the _force_ must be very heavy;” p. 71. “B, a barrel of iron or brass, fastened in the midst of the cistern, with a _force_ fitted unto it;” p. 72. “The _force_ is linked, and it is noted with the letter D,” (in the engraving.) Again, “F, the barrel of the _force_, fastened within two or three inches of the bottom of the cistern;” p. 73, “C, a _force_, D, the _forces_ barrel.” Again, “the _force_ draweth the water out of the cistern B, into the barrel D;” p. 74, “another strong iron bar as I I, unto each end whereof must be linked a _force_; K K, the two barrels of the aforesaid _forces_.” In the 21st volume of Philosophical Transactions, published in 1700, there is a description, with an engraving,[M] being, “An account of Mr. Thomas Savery’s engine for raising water by the help of fire.” It states that Mr. Savery, on the 14th of June, 1699:--“Entertained the Royal Society with shewing a model of his Engine for raising water by the help of fire, which he set to work before them; the experiment succeeded according to expectation, and to their satisfaction. The Engine may be understood by the draughts of it, where Fig. 1 is the front of the Engine for raising water by fire; and Fig. 2, the side prospect of the Engine. “A, is the furnace; B, the boiler; C, two cocks which convey the steam from the bottom in order to discharge it again at the top; D, which convey the steam by turns, to the vessel D. the vessels which receive the water from the bottom in order to discharge it again at the top; E, valves; F, cocks which keep up the water, while the valves on occasion are cleaned; G, the force pipe; H, the sucking pipe; and I, the water.” [Illustration: Savery’s Engine, 1699] Neither at the time nor afterwards does the invention appear to have attracted any further notice in that quarter. The next account we have of it is afforded by “The Miners Friend, or an Engine to raise Water by Fire,” by Thomas Savery, Gent., 1702; in which the invention appears with two furnaces, instead of one, and with other details. In his description he refers to two vessels, marked P, No. 1, and P, No. 2, which correspond with the two receivers above, marked D, D.