Read the first article.
The text is taken from the Library of Congress' American Memory site (http://memory.loc.gov/ammem/index.html).
The Pneumatic Rolling-Sphere Carrier Delusion.
BY DR. P. H. VAN DER WEYDE.
SECOND ARTICLE.
Manufacturer and Builder Magazine, Volume 22, Issue 11, November 1889
The pneumatic dispatch systems are closely allied to the pneumatic or atmospheric railways, because they are operated by the same agency -- air pressure. It is, therefore, proper to refer to both of them, especially as the improvements in the latter have had a useful influence in the development of the former.
Very soon after the invention of the air pump by Otto von Guericke, in Germany, in 1655, it was found that small objects could be propelled by atmospheric pressure through a tube of which one end was open, while the other end was connected with an air pump. It was, in fact, for many years a favorite lecture-room experiment to let a little ball ascend in an inclined glass tube, by exhausting the air at the upper end, and letting the ball roll down again by gravity when the air was admitted from above.
It was only after a lapse of 170 years, in 1825, that the first practical application was made of this discovery, by ValIance, of Brighton, England, who invented a device intended to transmit freight, and even passengers, by atmospheric pressure acting on a piston, or rallier diaphragm, fitting almost air-tight, in a square wooden tube. This piston was attached to a carriage on wheels, in which the freight or passengers were placed, while the air was exhausted by a stationary steam air pump placed at the forward end of the tube.
Ten years later (1835), Henry Pinkas placed carriages on rails outside of a round metallic tube, and connected the forward one, by means of a rod, with the piston inside the tube, while the latter had, on the upper side, a longitudinal slot, provided with a continuous elastic double valve, which gave passage to the piston rod, without admitting air. In 1840, Clegg and Samuda constructed such an arrangement on a portion of the West London Railway, which was considered such a success that it was adopted by the Dublin & Kingston Railway from Kingston to Dalkey, and, later, for 10 miles on the South Devon line. The English, and especially the French patent records commemorate a great number of improvements in the details of construction, according to which the St. Germain railway was established, and ran so successfully that it was still in operation in 1862. Later, it was also abandoned by reason of the enormous improvements made in locomotives, which soon took the lead universally, in spite of their deficiency of economy in the consumption of fuel.
The writer of this article saw, in 1849, the operation of a working model of such a railway, which was on exhibition in one of the leading hotels on Broadway, New York. It consisted in an inclined railway track, with a slotted tube between the rails, while a miniature train of cars was propelled upward by the sliding piston moved by the exhausting action of an air pump placed at the top of the incline.
The exhibition was intended as an attempt to introduce the system in the United States, but without success, not so much on account of any deficiency as for the need of a very different kind of invention of a later date, and which is successfully operated at the present day, especially in New York city. It consists in the formation of a stock company, which allows a liberal commission to any one who, by promise of great profits, can induce his rich friends or acquaintances to invest money in the affair by purchasing stock. In order to give this kind of business a lift, it is customary to sell at a very low figure, or, if necessary, to give outright without pay, several shares of stock to some prominent men, in order to have them on the list of stockholders. We mean such men as the Vice-President and Postmaster-General of the United States, the President of the Union Pacific Railroad, etc. This method was applied a few years ago, as is well known, by the Pan-Electric Telephone Company, of New Orleans, with the additional purpose of interesting influential members of the United States government on their side during the pending patent law suits which were anticipated. It is also customary to start rumors of offers made by certain capitalists of one, two, or more million dollars for the possession of the patent-rights, with the additional information that the offer was flatly refused by the company.
About the time (1861 or 1862) that I was occupied with the experimental investigation and theoretical consideration of the subject, I received at the Cooper Union a visit from Elms P. Needham, who was a manufacturer of the so-called parlor organs, or melodeons (at 264-268 East Twenty-third street, New York), and with whom I had become very well acquainted. He informed me that he had secured a patent covering two features of a system of pneumatic transmission of his invention, which were, first, the use of hollow rolling balls containing the materials to be transmitted; and, second, the combined use of compressed air behind the balls and rarified air in font of them. This he accomplished by a blowing arrangement, of which the exhaust tube was connected with the receiving box, and the blowing tube with the transmitter. He invited me to come to his establishment and examine the small working model which he had constructed, and which, he said, excited the astonishment of all who saw its successful operation. I did so, and found a series of mutually-connected glass tubes, of about an inch, or perhaps more, in diameter, forming a closed circuit as long as the large room admitted. In these tubes were contained loosely-fitting small balls, which were easily and smoothly propelled by the operation of an exhaust and compression blower, worked by hand. The whole arrangement was very neat, and well adapted to cause the wonder and praise of those ignorant of the operation of air pumps and the properties of compressed and rarefied air.
I frankly told him my opinion, and mentioned some objections to the rolling balls when applied on a large scale and filled with material to be transmitted, and advocated the construction of closely-fitting wagons, resting on interior wheels, slightly projecting through the bottom. I do not know whether this suggestion caused him to construct, later, the arrangement of a straight, square box of boards, 4 inches wide and as long as the size of his premises allowed (78 feet). In this box he had a small wagon, 8 inches long, in which he packed letters and papers, and found that it operated perfectly, as was to be expected, because he had a disposable surface to exert the pressure on of 16 square inches, which, if his air pump or blower had only the capacity of increasing the air pressure one-fifteenth and decreasing it at the other side as much, would give a pressure of 2 pounds per inch, or 82 pounds for the whole sectional surface -- much more than sufficient to accomplish the purpose.
In 1864, I left New York to accept a professorship offered me in Guard College, Philadelphia, and when, the following year (1865), I visited New York to see the exhibition at the yearly fair of the American Institute, then held in the Armory in Fourteenth street, I found there Elias P. Needham's pneumatic dispatch models in operation, while his brother, Orwell H. Needham, almost daily gave lectures and explanations on the advantages of this system, and he did this with considerable ability.
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