1847.1 



THE CIVIL ENGlNSilill AND ARCHITECTS JOURNAL. 



147 



of propelling in use in America, on the principle of the screw ; one plan was 

 to have a hollow in the bottom of the vessel nearly as long as the vessel it- 

 self, with a screw revolving in it to produce motion forwards or backwards ; 

 another form of this system was to have a double screw between two boats. 

 In 1825 a company was formed for applying Brown's gas vacuum engine to 

 navigating boats on canals, and a premium was offered for the best invention 

 for propelling boats without paddle-wheels. In 1827 the ingenious and in- 

 defatigable Tredgold, in his work on the steam engine, described and inves- 

 tigated the theory of screw propelling; about the same time, or perhaps 

 lather before, Brown, the inventor of the gas vacuum engine, proposed to 

 apply a propeller, consisting of two blades placed at an angle of about 90' 

 to each other and 45° to to the axis; this was intended to be placed in the 

 front of the bow of the vessel, and attached to a shaft working through a 

 stuffing-box, which could be raised or lowered at pleasure. He obtained the 

 premium of the Canal Towing Company for this, and they determined to 

 pursue the subject further ; in furtherance of this object, they built a vessel 

 at Rochester with a gas vacuum engine of 12 h.p., which was applied to 

 working Brown's propeller by means of bevil gear; the result of this exoeri- 

 ment does not exactly appear, althouuh it was considered sufficiently satis- 

 factory for Brown to continue his investigations : he accordingly built anotlicr 

 boat with similar engine and machinery, and made several experiments with 

 it on the Thames, near London, when he is said to have attained the velocity 

 of seven miles an hour with it. 



Subsequently, Cameron, Woodcroft, Lowe, Ericson, and others pursued the 

 subject and took out patents for various modifications ; nothing, however, was 

 materially effected until 183C, when T. P. Smith obtained a patent for the ap- 

 plication of a screw to propel vessels, by placing it in that part of the stern of 

 the vessel called the " dead wood." He accordingly builta small vessel, and 

 made numerous experiments with her on the Thames; this little vessel was 

 34 feet long, 6 feet 6 inches beam, and drew 4 feet water ; in it he placed a 

 small high-pressure engine, with a cylinder 6 inches in diameter, and 15 

 inches stroke, which was applied to working a screw 2 feet diameter, having 

 a pitch of 2 feet 5 inches. With this vessel he obtained a speed of from 7 

 to 8 miles an hour; he then tried her on the sea between Ramsgate and 

 London, and she answered very well in driving against the wind in a heavy 

 8ea. Upon the success of this experiment a Companv, called the Ship-Pro- 

 pelling Company, was formed, Smith being their adviser, and under his 

 directions a vessel, called the ' Archimedes,' of 232 tons burthen, was built 

 in London by Whimshurst; she was 125 feet long and 21 feet 10 inches 

 beam, having a draught of water of between 9 and 10 feet; she was pro- 

 pelled by a pair of engines of the united force of 80 h.p. The engines and 

 machinery, which were made by Messrs. Rennie, instead of being placed 

 transversely in the vessel as was usual in paddle-wheel steam boats, were 

 placed longitudinally ; these engines were upon the direct-acting principle, 

 and their power was applied to work the shaft upon which the propeller was 

 placed, by means of two spur-wheels with teeth of hornbeam wood, and two 

 pmions with iron teeth working into each other, the motion of the propeller 

 shaft being 5-33 to 1 ; or, in other words, when the engine made 25 strokes, 

 the propeller made 133-3 revolutions. The propeller, which was in the dead 

 ■wood, was united to the shaft, by means of a water-tight stuffing-box passing 

 through the stern of the vessel. The propeller at first consisted of a single- 

 threaded screw ; but this not answering so well, another screw was employ, 

 ed, with two threads opposite to each other, 5 feet 9 inches diameter, and'S 

 feet pitch. The ' Archimedes' obtained a velocity of 9 miles per hour through 

 the water, and proved herself an admirable sea-boat, going head to wind in 

 a heavy sea, and she established beyond all doubt the success of the inven- 

 tion, and its superiority over paddle-wheels in many cases; still, however, 

 much remained to be done before prejudice could he overcome, and before 

 the system could be brought to such perfection as to compete in velocity 

 successfully with paddle-wheels, which had so long and so completely en- 

 grossed the public attention as scarcely to leave an opening for any other 

 eystem ; latterly, however, screw propelling has made considerable progress. 

 In 1842, the 'Bee' was constructed by Maudslay and Field for the Govern, 

 ment; she was worked by a steam-engine of 10 h.p., adapted for driving 

 mther the screw or the paddle-wheel in the same vessel, and thus to try the 

 comparative merits of the two systems. From the trials and experiments 

 made with the • Bee,' it appeared, that upon the whole the paddle-wheels 

 had an advantage as to speed under all circumstances. In 1840, the ' Dwarf,' 

 of 210 tons burthen, which was the first screw vessel ever commissioned in 

 the British navy, was constructed by Messrs. Rennie; the engines, of 120 

 h.p., upon the direct action principle, were attached to two spur-wheels 

 with two pinions for working the screw upon the propeller shaft, on the 

 same plan as the 'Archimedes.' The ' Dwarf proved herself an excellent 

 sea boat, and attained a speed of 12} miles per hour through still water 

 The ' Rattler' was the second screw propelling vessel introduced into the 

 navy. She was 176 feet long, and 32 feet 8 inches beam ; drawing 11 feet 

 3 inches water, carrying 20 guns, and was about 888 tons burthen The 

 engines, of 200 h.p., were by Messrs. Maudslay and Field ; and her screw 

 which was 10 feet diameter, and 11 feet pitch, was driven by cog-wheels • 

 the screw made 103 revolutions per minute, being in the proportion of 4 to' 

 1 of the speed of the engines ; her velocity through still water was 9A miles 

 per hour, and she proved a good sea boat. All these have been surpassed 

 in speed by the Royal yacht, the ' Fairy,' built for her Majestv, by Ditchburn 

 with engines by Penn ; she is 2C0 tons burthen, with two oscillating engines 

 of the united force of 12.5 h.p., driving one spur-wheel and one pinion ■ the 

 screw consists of two blades, and makes 250 turns per minute, being in the 



proportion of 5 to 1 of the moving power. The speed of the ' Fairy' is 15 j 

 miles per hour through the water. The merits of the screw system have 

 now been so completely tested, that the Government have determined to in- 

 troduce it more generally into the navy, particularly for guard ships ; these 

 vessels are to be of two classes, line-of-hattle ships and frigates ; the former 

 having combined engines of 550 h.p., the latter 350 h.p. ; the cylinders of 

 the engines will, in some cases, be applied horizontally, and the pistons will 

 act directly upon the propeller shafts, by cranks, without the intervention of 

 wheels ; the propeller shaft will make from 50 to 60 revolutions per minute, 

 and the speed of the vessels will be from 5 to 7 miles an hour ; this velocity 

 will he surticient to enable them to command their own position ; and with 

 heavy guns and the free uninterrupted use of their batteries, they will be 

 fully equal to cope with any vessels of their class. The ' Amphion' frigate is 

 also being fitted with a screw propeller, to move with a greater velocity than 

 the guard-ships. She is 1290 tons, was originally built for sailing, and car- 

 ries 36 guns ; she is propelled by a screw of two blades, 15 feet diameter, 

 and 21 feet pitch, driven by a pair of engines of 300 h.p., making from 45 to 

 50 revolutions per minute; her speed on trial was 7 knots an hour, and pro- 

 mised more ; the whole was designed and executed by Messrs. Miller and 

 Raveiihill. To Miller the constructive portion of marine engineering owes 

 much ; the forms of framing, the graceful proportions, and scientific com- 

 bination of strength with lightness : the arrangement of the several working 

 parts of the engines, so as to diminish the weight, and increase their com- 

 pactness, without impairing their efficiency, have produced the natural con- 

 sequences, not only in the fast river boats on the Thames and the Rhine, and 

 other rivers where peculiarities of construction werespecially demanded, but 

 also in the sea-going vessels, for the mercantile as well as for the Royal 

 Navy and the Post-office service of both France and England. 



Much discussion has already taken place, and is still going on, as to the 

 best form and dimensions of propellers ; nothing, however, but careful and 

 well-conducted experiments can determine this important point. In these 

 investigations Rennie has taken a leading part ; Smith, Lloyd, Sunderland, 

 Barlow, Guppy, Brunei, Airy, Maudslay, Field, Miller, Barnes, Penn, and 

 others have also done a great deal. Up to the present time the double- 

 bladed propeller has produced as good a result as any other form. In the 

 first application of steam power to screw, or stern propelling, cog-wheels 

 were usually employed to drive the propeller ; then straps, or bands, work- 

 ing upon wooden or iron cylinders ; and in the ' Great Britain,' endless chains 

 were employed; in this case, however, the chain had claws, resembling 

 teeth, attached lo it, which fitted into corresponding recesses or cavities, on 

 the drum, and to a certain degree, prevented the stretching or slipping to 

 which chains of the ordinary description are liable; adhesion wheels were 

 also tried by Messrs. Rennie, but were not found so good as cog-wheels. 

 Latterly the system has been much simplified, by applying the piston of the 

 engine to act directly upon the propeller shaft, and a successful result ap- 

 pears probable. Whilst upon this subject, the ' Great Britain,' the largest 

 vessel constructed in modern times, must not be omitted. She is 322 feet 

 long, 50 feet 6 inches beam, draws 16 feet of water, and is 3444 tons bur- 

 then. She is propelled by the screw, with a pair of engines of the united 

 force of 1000 h.p. ; there are four cylinders, inclining at an angle of 60", and 

 parallel with the keel ; the pistons act by means of cranks upon a large 

 wheel, which turns the drum with the chain and propeller shaft ; the dia. 

 meter of the screw is 15 feet 9 inches. She left Bristol on her first trial on 

 the 8th January 1845 ; and on the 23rd of the same month, for London and 

 Liverpool, — for New York on the 26th July, 1845, and reached that city on 

 the 10th August ; left New York on the 30th August, and reached Liverpool 

 on the 15th September. This vessel and her machinery may be considered 

 as a great experiment, from which useful results may be expected. She has 

 already made two voyages across the Atlantic ; and, notwithstanding the 

 prognostications of many as to her failure, according to the report of her 

 able and experienced commander. Captain Hosken, has answered well as a 

 sea boat. Since then her engines and machinery have undergone certain 

 modifications, and some trifling alterations have also been made in the ves- 

 sel, which experience has proved to be necessary, and which from the novelty 

 of the construction, and the great scale upon which the experiment was 

 tried, might have been expected, and for which every allowance should be 

 made. These alterations have improved her materially ; and it is greatly to 

 be desired that so much labour and expenditure should be attended with 

 complete success. This gigantic structure, which has bad the advantage of 

 Brunei's assistance, is certainly bold, original, and in the right direction; for 

 nothing but proportionable mass, power, and correctness of form, are caU 

 culated to contend with the heavy swell and gales of the Atlantic. It is by 

 these and other well conducted experiments, that we may look forward with 

 confidence, at no very distant period, to the voyage between America and 

 Europe, much as it has already been shortened, being still further reduced. 

 The same may be said of the voyage between India and Europe, the import- 

 ance of which cannot be too highly estimated. 



The advantage of steam, as an auxiliary to sailing vessels [in long voyages, 

 the steam power being only applied in calms, or when the wind is unfavour- 

 able, is beginning to be generally felt ; and numerous vessels are now being 

 fitted out upon this principle. For this purpose the screw propeller, with 

 the means of taking it out of the water and replacing it when required with- 

 out stopping the vessel, appears peculiarly well adapted; for whilst it enables 

 the vessel to retain all her sailing qualities, as well as her capability for 

 stowing cargo, it still gives her the advancage of steam power when neces- 

 sary. The steam power, as it is not intended to be the chief agent, should 



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