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Updated: May 2, 2025
Old ideals were passing away, and the heritage which the Nineteenth Century was able to pass on to the Twentieth was in preparation. In this preparation Ericsson bore a large and most important part. So long as ships traverse the seas, Ericsson's name will be remembered for his work in connection with the introduction of the screw-propeller.
As it is, the fact that he was so largely instrumental in their perfection and adaptation to marine uses is wellnigh forgotten in the brighter light of his other achievements. Regarding Ericsson's relation to the successful introduction of the screw-propeller, little need be added to what has already been said.
In alluding to Sir George, M. Berget says: "The inventor, the incontestable forerunner of aviation, was an Englishman, Sir George Cayley, and it was in 1809 that he described his project in detail in Nicholson's Journal.... His idea embodied 'everything' the wings forming an oblique sail, the empennage, the spindle forms to diminish resistance, the screw-propeller, the 'explosion' motor,... he even described a means of securing automatic stability.
If properly constructed, this toy acts with great force and certainty, and if the spinning motion could only be kept up, by any means, the ascent would be continued. The principal here involved is precisely the same as that which causes a windmill to turn, a screw-propeller to drive a ship, and a cork-screw to enter a cork. It is pressure against a resisting medium.
Then this memorial was remembered, and its author brought forward to receive his share of credit in connection with the adaptation of the propeller to marine propulsion. These various attempts to introduce the screw-propeller seem curiously enough to have had no lasting result.
F.P. Smith seems to have been drawn to the subject of the screw-propeller, and we find him taking out a patent for his form, consisting of an elongated helix or spiral of several turns, under date of May 31, 1836. Ericsson's patent followed some six weeks later, or on July 13, 1836.
From this point of view, the period in question has the character of an epoch, initiated, made possible, by the invention of the screw-propeller; which, in addition to the better nautical qualities associated with it, permitted the defence of the machinery by submersion, and of the sides of the ship by the application of armor.
As early as 1804, John Stevens, of Hoboken, New Jersey, engaged in experiments to devise some means of driving a vessel through the water by applying the motive power at the stern, and with a screw-propeller and a defective boiler attained for short distances a speed of seven knots; and it is surprising, that, with the genius and determination so characteristic of his race, he should have abandoned the path on which he appears to have so fairly entered.
We had thought of getting the theory of the screw-propeller from the marine engineers, and then, by applying our tables of air-pressures to their formulas, of designing air-propellers suitable for our purpose. But so far as we could learn, the marine engineers possessed only empirical formulas, and the exact action of the screw-propeller, after a century of use, was still very obscure.
These propellers, in fact, had a form far more nearly approaching the modern screw-propeller than did those which came somewhat later, and which marked the real entry of the screw-propeller into actual and practical service. Again, in 1812, Ressel, a student in the University of Vienna, began to study the screw-propeller, and his first drawing dates from this time.
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