SHIP. 



235 



to incapacitate it for holding her. To obviate this 

 inconvenience, it is usual to moor with two anchors, 

 one placed in the direction of the flood, the other 

 of the ebb tide. If there be no tides, the anchors 

 are opposed to the prevailing winds, the heaviest 

 being towards the most windy quarter. Should a 

 gale occur while thus moored, by veering out the 

 cable which holds the ship, both may be brought 

 ahead to act in concurrence. Care must ever be taken 

 to keep the hawse clear for thus veering, that is, 

 to prevent the ship from twisting her cables, by 

 turning always the same way ; or, when this un- 

 avoidably occurs, the hawse must be cleared by 

 unbinding one of the cables, and carrying it round 

 the other beneath the bow, until the turns be re- 

 moved. 



When about to sail, the hatches are carefully 

 calked down and tarpaulined, except those neces- 

 sary for the ascent and descent of the crew, and the 

 boats are stowed. You may now unmoor, prepar- 

 ing the first anchor for letting go before taking up 

 the second. If tending to the tide, with the wind 

 fair to pursue your course, the last anchor may also 

 be taken up and stowed before making sail. If, 

 however, as is usual, your ship lie head to wind, 

 stop heaving in when the cable is short, and pro- 

 ceed to make sail. The wind being moderate, the 

 courses, top-sails, top-gallant-sails, jib and spanker 

 may be loosed together; the top-sails and top-gal- 

 lant-sails are sheeted home and hoisted up ; and the 

 other sails hang ready to be called into action 

 whenever necessary. The yards are now braced 

 ready to cant the ship. If you wish her to go to 

 the right, the head yards are braced with their 

 right sides forward, and the afteryards the contrary 

 way. Hence the wind, striking the fore sails ob- 

 liquely on the left, tends to force them to the 

 right; and, on the contrary, the after sails, being 

 acted upon in an opposite direction, are forced to 

 the left ; but the fore sails are forward of the cen- 

 tre of rotation, while the after sails are abaft it; 

 consequently the efforts which they respectively 

 exert will tend, the first to force the ship's head to 

 the right hand, the others the stern to the left. 

 The sails thus trimmed, now heave up the anchor, 

 profiting of the trifling advance through the water 

 to turn the ship's head still more, and make the 

 angle of the wind with the keel more open, by the 

 action of the rudder. As soon as the anchor trips, 

 and the wind begins to force the ship sternward, 

 shift the rudder to the opposite side, that, by offer- 

 ing an obstacle on the left of the ship, the right 

 side may turn backward round it more rapidly. 

 This action of the rudder, in conjunction with the 

 sustained effort of the sails to turn the ship to the 

 right, and, presently, the addition of the jib, will 

 gradually make the wind more and more open on 

 the left bow, until at length it becomes sufficiently 

 'so to fill the after-sails, which have hitherto lain aback. 

 When this is the case, the fore yards are braced 

 full, the spanker and courses set, and the ship im- 

 mediately begins advancing. This mode of weigh- 

 ing is practised where there are other ships or a 

 shore to leeward; otherwise it is more common not 

 }o hoist the jib, or fill the fore sails, until the anchor 

 is raised to the cat-head. The ship being under 

 weigh, the time occupied in clearing the harbour 

 is employed in stowing the anchors, unbending the 

 cables, if the nature of the coast render it safe to 

 do so, applying mats to the rigging and yards, to 

 prevent chafing, and in securing the boats, water- 

 casks, and whatever other movable objects might 



be in danger of starting by the pitching and rolling 

 of the ship. 



Our ship is now at sea, and it only remains to us 

 briefly to explain the manner in which she is pro- 

 pelled and governed, and made obedient to her crew. 

 There is no difficulty in conceiving how a ship may 

 be made to move before the wind through a quies- 

 cent fluid like the sea. Let us suppose one at rest 

 in a perfect calm, and equally pressed on every side 

 by the gravitating action of the same fluid : she is 

 maintained in equilibrio. But, by and by, a wind 

 rising behind her, strikes her sails perpendicularly, 

 and exerts a pressure in a single direction. As, 

 however, the sails are attached to spars, and these 

 in turn to the ship, it is evident that they cannot 

 obey the impulse independently of the ship, but 

 that all must move in unison; and the ship, 

 being before pressed by the water equally, and 

 maintained in quiescence, requires but a slight addi- 

 tional pressure in any direction to destroy her equili- 

 brium. This pressure is abundantly supplied by 

 the air of our atmosphere; for, though little more 

 than a thousandth part the density of the sea, it 

 may receive a velocity enabling it to strike the sails 

 with its particles in such quick succession as to 

 force the ship forward with great rapidity, and, if 

 the resistance of the water check her escape before 

 it, may even act with sufficient power to blow away 

 the strongest sails, or even tear the masts out. 

 Thus a beneficent Nature, in providing an element 

 essential to our existence, by subjecting it to laws 

 requisite for its healthy preservation, and forming a 

 necessary link in the universal economy, has at the 

 same time supplied an ever-active agent, which the 

 ingenuity of man an emanation of the same great 

 Intelligence has rendered subservient to the no- 

 blest purposes. 



Conceiving, now, how it is possible for a ship to 

 move freely before the wind, with a velocity de- 

 termined by the force of that wind, the quantity of 

 sail exposed to it, and the adaptation of her form to 

 divide the sustaining fluid with the least resistance, 

 we will now show how it is also possible for her to 

 move in directions other than directly before the 

 wind, and even to approach it. Let us suppose that 

 the wind, at first dead aft, gradually veers towards 

 the side, until it blows at an angle of forty-five de- 

 grees with the keel. If, with the wind thus blow- 

 ing, I still preserve my sails braced perpendicular- 

 ly to the keel, it must necessarily strike their sur- 

 faces obb'quely, dividing itself into two forces, one 

 passing off to leeward, the other exerting itself in 

 the direction of the keel, and therefore tending to 

 propel her forward. If, however, in order to ex- 

 pose my sails more fairly to the wind, I brace them 

 forward until it becomes again perpendicular to 

 their surfaces, the action of the wind on the sails 

 is simple, but that of the sails on the ship is in turn, 

 compound, subdividing itself into two forces; one 

 acting to drive her to leeward in a direction perpen- 

 dicular to the keel; the other, forward in a line 

 with it. If, now, the ship were of a figure to 

 move with equal freedom in any direction round, 

 for instance it is evident that she would assume a 

 mean motion between these two forces ; but, being 

 so formed as to divide the water with infinitely 

 greater difficulty sidewise than forwards, the force 

 exerting itself perpendicularly to the keel is neu- 

 tralized, whilst that in a line with it, encountering 

 an inferior resistance, compels the vessel to advance. 

 We will next suppose the wind to have drawn for- 

 ward until perpendicular to the course. The sails. 



