Smith, however, arrived at the conclusion that his method of propelling steam vessels by means of a screw was much superior to paddles--at that time exclusively employed. In the following year, 1835, he constructed a superior model, with which he performed a number of experiments at Hendon. In May 1836, he took out a patent for propelling vessels by means of a screw revolving beneath the water at the stern. He then openly exhibited his invention at the Adelaide Gallery in London. Sir John Barrow, Secretary to the Admiralty, inspected the model, and was much impressed by its action. During the time it was publicly exhibited, an offer was made to purchase the invention for the Pacha of Egypt; but the offer was declined.
At this stage of his operations, Smith was joined by Mr. Wright, banker, and Mr. C. A. Caldwell, who had the penetration to perceive that the invention was one of much promise, and were desirous of helping its introduction to general use. They furnished Smith with the means of constructing a more complete model. In the autumn of 1836, a small steam vessel of 10 tons burthen and six horse-power was built, further to test the advantages of the invention. This boat was fitted with a wooden screw of two whole turns. On the 1st of November the vessel was exhibited to the public on the Paddington Canal, as well as on the Thames, where she continued to ply until the month of September 1837.
During the trips upon the Thames, a happy accident occurred, which first suggested the advantage of reducing the length of the screw. The propeller having struck upon some obstacle in the water, about one-half of the length of the screw was broken off, and it was found that; the vessel immediately shot ahead and attained a much greater speed than before. In consequence of this discovery, a new screw of a single turn was fitted to her, after which she was found to work much better.
Having satisfied himself as to the eligibility of the propeller in smooth water, Mr. Smith then resolved to take his little vessel to the open sea, and breast the winds and the waves.
Accordingly, one Saturday in the month of September 1837, he proceeded in his miniature boat, down the river, from Blackwall to Gravesend. There he took a pilot on board, and went on to Ramsgate. He passed through the Downs, and reached Dover in safety. A trial of the vessel's performance was made there in the presence of Mr. Wright, the banker, and Mr. Peake, the civil engineer. From Dover the vessel went on to Folkestone and Hythe, encountering severe weather. Nevertheless, the boat behaved admirably, and attained a speed of over seven miles an hour.
Though the weather had become stormy and boisterous, the little vessel nevertheless set out on her return voyage to London.
Crowds of people assembled to witness her departure, and many nautical men watched her progress with solicitude as she steamed through the waves under the steep cliffs of the South Foreland.
The courage of the undertaking, and the unexpected good performance of the little vessel, rendered her an object of great interest and excitement as she "screwed" her way along the coast.
The tiny vessel reached her destination in safety. Surely the difficulty of a testing trial, although with a model screw, had at length been overcome. But no! The paddle still possessed the ascendency; and a thousand interests--invested capital, use and wont, and conservative instincts--all stood in the way.
Some years before--indeed, about the time that Smith took out his patent--Captain Ericsson, the Swede, invented a screw propeller.
Smith took out his patent in May, 1836; and Ericsson in the following July. Ericsson was a born inventor. While a boy in Sweden, he made saw mills and pumping engines, with tools invented by himself. He learnt to draw, and his mechanical career began. When only twelve years old, he was appointed a cadet in the Swedish corps of mechanical engineers, and in the following year he was put in charge of a section of the Gotha Ship Canal, then under construction. Arrived at manhood, Ericsson went over to England, the great centre of mechanical industry. He was then twenty-three years old. He entered into partnership with John Braithwaite, and with him constructed the Novelty, which took part in the locomotive competition at Rainhill on the 6th October, 1829. The prize was awarded to Stephenson's Rocket on the 14th; but it was acknowledged by The Times of the day that the Novelty was Stephenson's sharpest competitor.
Ericsson had a wonderfully inventive brain, a determined purpose, and a great capacity for work. When a want was felt, he was immediately ready with an invention. The records of the Patent Office show his incessant activity. He invented pumping engines, steam engines, fire engines, and caloric engines. His first patent for a "reciprocating propeller" was taken out in October 1834. To exhibit its action, he had a small boat constructed of only about two feet long. It was propelled by means of a screw;and was shown at work in a circular bath in London. It performed its voyage round the basin at the rate of about three miles an hour. His patent for a "spiral propeller," was taken out in July 1836. This was the invention, to exhibit which he had a vessel constructed, of about 40 feet long, with two propellers, each of 5 feet 3 inches diameter.
This boat, the Francis B. Ogden, proved extremely successful.