605 



STEAM NAVIGATION. 



STEAM-VESSEL. 



their voyages. Hence, every advantage which can be taken to accom- 

 plish this, is considered part of a commander's duty and his position, 

 therefore, depends much upon his habitually making a quick passage. 



The following will explain the work of each kind of navigator. In 

 tin- sailing ship, the master daily at 1 bell in the forenoon watch (half- 

 past Sa.ru.) takes his sextant upon deck to obtain an altitude of the sun, 

 in readiness for working his time at ship : he defers this work till noon, 

 at which he will have obtained his ship's latitude from a meridian alti- 

 tude. During the forenoon, or from nine o'clock, his only work con- 

 nected with navigation-proper, is an occasional glance over the side of 

 the ship, in order to estimate the ship's " way " (velocity), and also at 

 times at the binnacle compass to get an opinion as to the accuracy of 

 the course about to be marked on the log-board. [DEAD-ItECKO.xixi:.] 

 The ship's position at noon having been pricked off upon a chart, and 

 the log duly written up as soon after noon as convenient, the remainder 

 of the day calls for no further computations, unless, as it occasionally 

 happens, sights for the time were not procurable in the forenoon, an. 1 

 are taken at about 3 p.m, it being better to obtain them when the sun 

 is about three hours from the meridian. Occasionally, a sailing navi- 

 gator may see fit to try a lunar for his longitude, but this is entirely 

 optional ; or, perchance, in the evening an intelligent merchant captain 

 may desire to verify his position by observation of a star, &c. So then 

 as regards routine observation, the work of a sailing commander is 

 very light For even, if in addition to his daily routine he be approach- 

 ing laud, it entails no serious loss or labour to " lie-to " for a few hours 

 till daylight. 



Uut with a commander of a steamer, navigation ia quite another 

 thin;;; for in the first place, where a sailing commander deems it 

 advisable not to close in with the land towards nightfall, because he 

 U upon the wind only, a change in which might suddenly place 

 him on a lee shore ; the steam commander would, as a matter of duty, 

 take the shortest route, in whatever direction that might lie. It 

 will then 1* evident that with a vessel of greater comparative speed, 

 oft. 'ii using the more dangerous passage along a coast, her commander 

 should be a man of increased nautical skill, and of special proficiency 

 in navigation the latter attainment being the more needed as he lias 

 scarcely the discretionary power to " lay-to," except under special 

 circumstances. The stranding of a sailing ship may often be the 

 result of sheer accident of wind or weather, while that of a steamer, 

 which is locomotive, and can steer readily in any direction (in moderate 

 weather), baa been in too many instances found to have its cause in at 

 least error in judgment. 



To make the distinction between steam navigation and sailing 

 navigation the plainer, we will suppose a case, as applicable to the 

 following imaginary chart and track : 



Sfir.lt of Mi/c, 



Two vessels, the one sailing and the other steaming, are bound round 



the headland, g, of a> continent. There are several outlying daiiL'' is 



near it, such as the island ', the rocks at <l, the shoal at e, ami in 



addition, rocky spits nm off the points r anil / Suppose the two 



. to lie in company at a, and each desirous of reaching the 



n A : the steamer would, as a matter of course, take the inner 



jaiaigli, in whatever direction the wind might blow, while if the wind 



were as indicated by the arrow in the diagram, the (ailing ship could 



ntiirf, l.nt must take the outer passage and aa a square-rigged 



ship can only sail within about six points of the wind, her track in 



working to windward or " tacking," would in this case between o and 



thiity mil.*, while the steamer's would be about twelve. 



f we compare the two tracks it will be evident that the mind of 



ding master might well be free from care, except when approach- 



ing e, or the weather side of / ; while during the whole passage, through 

 a slight mistake or inattention on the part of the steam commander, 

 he might lose the ship. Suppose farther, that just as the steamer 

 reached her position near rf, the weather became hazy or foggy, 

 obscuring the land : the master of the sailing ship in the offing co;ild 

 without a care lay-to with the ship's head off the land, while the 

 steamer must push on, if possible; because anchoring would incon- 

 veniently delay her passage. He would have in such case to prick off 

 his actual position on his chart by hasty beariugs, subject to the delay 

 of correction for local attraction, &c., and indeed his work of navigation 

 would form a perfect contrast to that of the ship-master outside. 

 Farther investigation will even heighten the contrast, for in a passenger 

 steamer, the commander finds the necessity of verifying his position as 

 often as possible, by night as well as by day. He takes a larger 

 number of observations, and needs every accomplishment which 

 nautical astronomy offers him. 



If then such disparity exist in the duties of certain maritime com- 

 manders, and if, moreover, no amended system of training have been 

 yet perfected under authority, calculated to meet the increased in- 

 telligence called for by the exigence of steam navigation, the subject is 

 worthy of most earnest atteution. 



An impression is gaining ground among experienced commanders 

 themselves, that whereas other professions have their training based 

 upon principles which are carefully explained to them, the navigator 

 is consigned to work with formula; of which he has no comprehension. 

 beyond their mere adaptation to his work. Trigonometry, plane and 

 spherical, is the foundation of all his calculations, but neither are its 

 principles explained in schools of navigation generally, nor is even 

 the projection of its figures deemed important. In the Royal Xaval 

 School, and one or two others, this great defect has been of late 

 attended to, and their example cannot, for the good of the community, 

 be too soon followed by those who have had the training of nearly 

 50,000 of our population whose profession is that of the sea officer. 

 That our sea captains are successful in their voyages as a general rule, 

 depends on their perseverance and intelligence as a body : they com- 

 plain that they owe little to science and teaching. 



With regard to spheric trigonometry, circumstances already ex- 

 plained under <!i'.i .\T-CiRC'i,K-S.ULiNO have strangely driven it from 

 i-vi-ii the " Manual" of the Navigator. [SPHERICS ; SPUEROGRAPH.] 



(IJaper's Treatise wi \nri>j<tt<i>u ; Jean's \Vorks on Trigonometry; 

 The Calculation and Projection of the Sphere, Longman & Co.) 



STEAM-VESSEL, a vessel moved by the power of a steam-engine 

 acting upon paddle-wheels or other mechanism for propelling it through 

 the water. Under SHIP, SHIP-BUILDING, &c., were explained the prin- 

 ciples on which vessels are constructed; and under STEAM, STKAM- 

 K.xtiiN-i:, PROPELLER, &c., have been described the means of propulsion. 

 Before entering upon the construction of steam-vessels, we give a brief 

 notice of the rise and progress of the application of steam to navigation. 



A curious claim has been brought forward on behalf of Blasco de 

 Garay, a sea captain, who is stated to have exhibited in Spain, in 1543, 

 an engine by which ships and vessels of the largest size could be pro- 

 pelled, even in a calm, without the aid of oars or sails. The documents 

 relating to this claim, which, if correct, gives Spain the priority by a 

 long period in experiments on steam navigation, were discovered in the 

 royal archives at Simancas, and were published in 1820, by Thomas 

 Gonzales, director of the archives. 



Stuart, in his ' Anecdotes of Steam-Engines,' endeavours to establish 

 something like a claim to tho invention of steam navigation by the 

 Marquess of Worcester. The author alludes to a little engine, or great 

 model, which he had " already erected " at Lambeth ; and among many 

 other purposes to which his invention might bo applied, states that it 

 may be used " to draw or hale ships, boates, &c. up rivers against tbo 

 streame; to draw carts, wagons, &c. as fast without cattel ; to draw 

 the plough without cattel, to the same despatch if need be," &c. 



The project to be next alluded to is that of Papin, who proposed an 

 apparatus somewhat like that subsequently patented in England by 

 Jonathan Hulls. Those who have endeavoured to establish a claim 

 to the invention of steam navigation on behalf of France, have 

 pleaded I'apin's suggestion in favour of their views ; but none, so 

 far as we know, have asserted that he put his scheme to the test of 

 experiment. 



On December 21, 173G, a patent was granted to Jonathan Hulls for 

 a machine which may be designated a steam tug-boat; of which a full 

 description was published in the following year, in a sensible pamphlet, 

 entitled ' A Description and Draught of a new-invented Machine for 

 carrying Vessels or Ships out of or into any Harbour, Port, or River, 

 against Wind and Tide, or in a Calm.' Hulls proposed to place an 

 >heric steam-engine in the tug-boat, and to communicate its 

 power by means of ropes to the axis of a kind of paddle-wheel mounted 

 in a frame-work projecting from the stern of the vessel. A contrivance 

 is added for continuing the motion of the paddles by the descent of a 

 counterbalance-weight, in the intervals between the strokes of the 

 piston. To guard against the injury of the fans or paddles by the 

 violence of tho waves, Hulls proposed to lay pieces of timber so as to 

 swim on each aide of them. The objections likely to be brought 

 against tho scheme are anticipated and answered by the writer, who 

 expresses his opinion that it would be found better to place tho 

 machine in a separate vessel than in the ship itself, because the 



