قراءة كتاب Scientific American Supplement, No. 620, November 19,1887
تنويه: تعرض هنا نبذة من اول ١٠ صفحات فقط من الكتاب الالكتروني، لقراءة الكتاب كاملا اضغط على الزر “اشتر الآن"

Scientific American Supplement, No. 620, November 19,1887
the vessel took place exactly eighteen months from the signing of the contract. Not only is this the fastest war cruiser afloat, but her owners also possess in the El Destructor what is probably the simplest torpedo catcher afloat, a vessel which has attained a speed of 22½ knots, or over 26 miles, per hour.—Engineering.
OLIVER EVANS AND THE STEAM ENGINE.
A correspondent of the New York Times, deeming that far too much credit has been given to foreigners for the practical development of the steam engine, contributes the following interesting resume:
Of all the inventions of ancient or modern times none have more importantly and beneficently influenced the affairs of mankind than the double acting high pressure steam engine, the locomotive, the steam railway system, and the steamboat, all of which inventions are of American origin. The first three are directly and the last indirectly associated with a patent that was granted by the State of Maryland, in 1787, being the very year of the framing of the Constitution of the United States. In view of the momentous nature of the services which these four inventions have rendered to the material and national interests of the people of the United States, it is to be hoped that neither they nor their origin will be forgotten in the coming celebration of the centennial of the framing of the Constitution.
The high pressure steam engine in its stationary form is almost ubiquitous in America. In all great iron and steel works, in all factories, in all plants for lighting cities with electricity, in brief, wherever in the United States great power in compact form is wanted, there will be found the high pressure steam engine furnishing all the power that is required, and more, too, if more is demanded, because it appears to be equal to every human requisition. But go beyond America. Go to Great Britain, and the American steam engine—although it is not termed American in Great Britain—will be found fast superseding the English engine—in other words, James Watt's condensing engine. It is the same the world over. On all the earth there is not a steam locomotive that could turn a wheel but for the fact that, in common with every locomotive from the earliest introduction of that invention, it is simply the American steam engine put on wheels, and it was first put on wheels by its American inventor, Oliver Evans, being the same Oliver Evans to whom the State of Maryland granted the before mentioned patent of 1787.
He is the same Oliver Evans whom Elijah Galloway, the British writer on the steam engine, compared with James Watt as to the authorship of the locomotive, or rather "steam carriage," as the locomotive was in those days termed. After showing the unfitness of Mr. Watt's low pressure steam engine for locomotive purposes, Mr. Galloway, more than fifty years ago, wrote: "We have made these remarks in this place in order to set at rest the title of Mr. Watt to the invention of steam carriages. And, taking for our rule that the party who first attempted them in practice by mechanical arrangements of his own is entitled to the reputation of being their inventor, Mr. Oliver Evans, of America, appears to us to be the person to whom that honor is due." He is the same Oliver Evans whom the Mechanics' Magazine, of London, the leading journal of its kind at that period, had in mind when, in its number of September, 1830, it published the official report of the competitive trial between the steam carriages Rocket, San Pariel, Novelty, and others on the Liverpool and Manchester Railway.
In that trial the company's engines developed about 15 miles in an hour, and spurts of still higher speed. The Magazine points to the results of the trial, and then, under the heading of "The First Projector of Steam Traveling," it declares that all that had been accomplished had been anticipated and its feasibility practically exemplified over a quarter of a century before by Oliver Evans, an American citizen. The Magazine showed that many years before the trial Mr. Evans had offered to furnish steam carriages that, on level railways, should run at the rate of 300 miles in a day, or he would not ask pay therefor. The writer will state that this offer by Mr. Evans was made in November, 1812, at which date not a British steam carriage had yet accomplished seven miles in an hour.
In 1809 Mr. Evans endeavored to establish a steam railway both for freight and passenger traffic between New York and Philadelphia, offering to invest $500 per mile in the enterprise. At the date of his effort there was not a railway in the world over ten miles long, nor does there appear to have been another human being who up to that date had entertained even the thought of a steam railway for passenger and freight traffic. In view of all this, is it at all surprising that the British Mechanics' Magazine declared Oliver Evans, an American, to be the first projector of steam railway traveling? In 1804 Mr. Evans made a most noteworthy demonstration, his object being to practically exemplify that locomotion could be imparted by his high pressure steam engine to both carriages and boats, and the reader will see that the date of the demonstration was three years before Fulton moved a boat by means of Watt's low pressure steam engine. The machine used involved the original double acting high pressure steam engine, the original steam locomotive, and the original high pressure steamboat. The whole mass weighed over twenty tons.
Notwithstanding there was no railway, except a temporary one laid over a slough in the path, Mr. Evans' engine moved this great weight with ease from the southeast corner of Ninth and Market streets, in the city of Philadelphia, one and a half miles, to the River Schuylkill. There the machine was launched into the river, and the land wheels being taken off and a paddle wheel attached to the stern and connected with the engine, the now steamboat sped away down the river until it emptied into the Delaware, whence it turned upward until it reached Philadelphia. Although this strange craft was square both at bow and stern, it nevertheless passed all the up-bound ships and other sailing vessels in the river, the wind being to them ahead. The writer repeats that this thorough demonstration by Oliver Evans of the possibility of navigation by steam was made three years before Fulton. But for more than a quarter of a century prior to this demonstration Mr. Evans had time and again asserted that vessels could be thus navigated. He did not contend with John Fitch, but on the contrary tried to aid him and advised him to use other means than oars to propel his boat. But Fitch was wedded to his own methods. In 1805 Mr. Evans published a book on the steam engine, mainly devoted to his form thereof. In this book he gives directions how to propel boats by means of his engine against the current of the Mississippi. Prior to this publication he associated himself with some citizens of Kentucky—one of whom was the grandfather of the present Gen. Chauncey McKeever, United States Army—the purpose being to build a steamboat to run on the Mississippi. The boat was actually built in Kentucky and floated to New Orleans. The engine was actually built in Philadelphia by Mr. Evans and sent to New Orleans, but before the engine arrived out the boat was destroyed by fire or hurricane. The engine was then put to sawing timber, and it operated so successfully that Mr. Stackhouse, the engineer who went out with it, reported on his return from the South that for the 13 months prior to his leaving the engine had been constantly at work, not having lost a single day!
The reader can thus see the high stage of efficiency which Oliver Evans had imparted to his engine full 80 years ago. On this point Dr. Ernst Alban, the German writer on the steam engine, when speaking of the high pressure steam engine, writes: "Indeed, to such perfection did he [Evans] bring it, that Trevithick and Vivian, who came after him,