United States or Libya ? Vote for the TOP Country of the Week !
Stephenson also, finding that the boiler would bear a greater pressure than five pounds to the inch, determined to work it at a pressure of ten pounds, though this was contrary to the directions of both Newcomen and Smeaton. The necessary alterations were made in about three days, and many persons came to see the engine start, including the men who had put her up.
More than once his health failed, and often the brave spirit was almost broken, as when he exclaimed in heaviness of heart, "Of all the things in the world, there is nothing so foolish as inventing." Five years had passed since the model of the Newcomen engine had been sent to him for repair before he succeeded in securing a patent on his own invention.
If Bishop Hall, when he first saw the treatise, and perceived its literary ability, "blushed for his age" that so "scandalous" a thing should have appeared, and if even Howell the letter-writer, in his prison, thought it the impudent production of "a poor shallow-brained puppy," what could Milton's orthodox and reverend Smectymnuan friends Marshall, Calamy, Young, Newcomen, and Spurstow think or say about it?
Watt having closed the top of the cylinder to save steam, was debarred from using water on the upper surface of the piston as Newcomen did, to fill the interstices between piston and cylinder and prevent leakage of steam, as his piston was round and passed through the top of the cylinder.
One can perhaps imagine the feelings with which James Watt, interested from his youth in mechanical and scientific instruments, particularly those which dealt with steam, regarded this Newcomen engine. Now his interest was vastly quickened.
For this purpose the Newcomen engine, in its then state, was found insufficient; and when Dr. Roebuck's friend, Professor Black, of Edinburgh, informed him of a young man of his acquaintance, a mathematical instrument maker at Glasgow, having invented a steam-engine calculated to work with increased power, speed, and economy, compared with Newcomen's; Dr.
Great pains were taken by Watt that this should be perfect, as so much depended upon a successful start. Many concerns suspended work upon Newcomen engines, countermanded orders, or refrained from placing them, awaiting anxiously the performance of this heralded wonder, the Watt engine.
For the explosion of the gunpowder he substituted the generation and condensation of steam, heating the bottom of his cylinder by a fire; a small quantity of water contained in it was vaporized, and then on removing the fire the steam condensed and the piston was forced down. This was substantially the Newcomen steam engine, but without the separate boiler.
The Newcomen engine consumed twenty-eight pounds of coal per horse-power and made not exceeding three to four strokes per minute, the piston moving about fifty feet per minute. To-day, steam marine engines on one and one-third pounds of coal per horse-power the monster ships using less make from seventy to ninety revolutions per minute. "Destroyers" reach 400 per minute.
It was to save this that the condenser was invented, in obedience to Watt's law, as stated in his patent, that "the cylinder should be kept always as hot as the steam that entered it"; but it must be kept clearly in mind that Watt's "modified machines," under his first patent, only used steam to do work upon the upward stroke, where Newcomen used it only to force up the piston.
Word Of The Day