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acting action added admit advantage air pump allow aperture applied atmospheric becomes body boiler boiling bottom calculation capacity Carbon cause chimney circular inch close coal cock column common condenser consequently considerable considered construction contain cooling cubic foot cylinder diameter direction double effect elastic force equal expansion experiments feet fire four friction fuel given gives greater half heat hence horses hour inches inches of mercury increase iron length less liquid loss lower manner means metal method minute mode motion moving multiplied nearly necessary obtained passage passing pipe piston Plate pounds practice pressure produce proportion quantity raised reduced regulated render resistance result rule shewn side slide space specific square steam engine stroke supply surface temperature tube valve vapour velocity vessel volume weight wheel whole
Page xix - An admirable and most forcible way to drive up water by fire, not by drawing or sucking it upwards, for that must be as the philosopher calleth it, infra spheeram activitatis, which is but at such a distance. But this way hath no bounder, if the vessels be strong enough ; for I have taken a piece of a whole cannon, whereof the end was burst, and filled it...
Page 20 - I call the steam vessel, must, during the whole time the engine is at work, be kept as hot as the steam that enters it ; first, by inclosing it in a case of wood, or any other materials that transmit heat slowly; secondly, by surrounding it with steam or other heated bodies; and thirdly, by suffering neither water nor any other substance colder than the steam to enter or touch it during that time.
Page xx - I have seen the water run like a constant fountain stream forty feet high. One vessel of water rarefied by fire driveth up forty of cold water ; and a man that tends the work is but to turn two cocks, that, one vessel of water being consumed, another begins to force and refill with cold water, and so successively, the fire being tended and kept constant, which the self same person may likewise abundantly perform in the interim, between the necessity of turning the said cocks.
Page xx - ... by fire driveth up forty of cold water. And a man that tends the work is but to turn two cocks, that, one vessel of water being consumed, another begins to force and re-fill with cold water, and so successively, the fire being tended and kept constant, which the self-same person may likewise abundantly perform in the interim, between the necessity of turning the said cocks.
Page 11 - A Description and Draught of a new-invented Machine, for carrying Vessels or Ships out of, or into, any Harbour, Port, or River, against Wind and Tide, or in a calm.
Page 20 - Fourthly, I intend, in many cases, to employ the expansive force of steam to press on the pistons, or whatever may be used instead of them, in the same manner as the pressure of the atmosphere is now employed in common fire engines.
Page 21 - In these steam-vessels are placed weights, so fitted to them as to fill up a part or portion of their channels, yet rendered capable of moving freely in them by the means hereinafter mentioned or specified. When the steam is admitted in these engines between these weights and the valves, it acts equally on both, so as to raise the weight...
Page 53 - ... of an inch upon the top of the mercurial column ; because being lighter it ascends by the side of the tube ; which may now be inclined and the mercury will rise to the top manifesting a perfect vacuum from air. I next take a cylindrical glass...
Page 20 - ... any other substance colder than the steam to enter or touch it during that time. " Secondly. In engines that are to be worked wholly or partially by condensation of steam, the steam is to be condensed in vessels distinct from the steam...
Page 21 - When the steam is admitted in these engines between these weights and the valves, it acts equally on both, so as to raise the weight to one side of the wheel, and by the reaction on the valves successively, to give a circular motion to the wheel, the valves opening in the direction in which the weights are pressed, but not in the contrary ; as the steam vessel moves round, it is supplied with steam from the boiler ; and that which has performed its office may either be discharged by means of condensers...