1017 



TACKING. 



TACKING. 



101S 



the hill in its abruptness, we sidle along upwards in a zig-zag direc- 

 tion until the summit is reached, and thus it is with tacking at sea ; 

 where, however, we use horizontal angles instead of the vertical ones 

 on land. 



The motion of a ship in thus beating to windward (as the whole 

 evolution is called) is considerably affected by the form of the ship 

 herself ; for barges, and flat or round-bottom vessels make great lee- 

 way, or are driven bodily from the wind, and the actual course sailed 

 is upon a line which is the resultant of two forces. For supposing 

 the wind to be acting in the direction indicated by the arrow in the 

 diagram, its power upon the mass of broadside and sails will have a 



tendency to drive it from A towards B (this is called leeway), while the 

 action of the sails in their obliquity to the keel drives the body also 

 forward in the line of keel AC. Now compounding these two forces, 

 A B and c D, we have the parallelogram A D as the resultant, while the 



amount of leeway would be measured by AB, and its angle would be 

 KAK. Hence tacking is more advantageous to sharp-bottomed vessels 



with a rising floor like yachts, cutters, &c., as they offer more vertical 

 resistance to the water in arresting the lateral drift AB. _ Vessels 

 having no keel or deadwood are generally furnished with what is called 

 a " lee-board," which working on a strong pin, as at in the figure, is 

 et down below the bottom on the lee side to prevent too much leeway 

 when tacking to windward. 



In order to very briefly explain the operation of tacking (or as it is 

 also called " heaving about "), suppose the figure below to represent a 

 ship at a, beating towards the direction of the wind x, and close hauled 



on the port tack accordingly, the tiller is put over towards y (" hard 

 a-lee "), which causes the rudder to bring the ship's head to wind, as 

 at b, or throws her into " stays; " just before she reaches this position, 

 the afteryards (on the main and mizen masts) are hauled aback and 

 then braced as at c, and as soon as the ship's head is found to be about 

 five points from the wind the head yards are braced round likewise, 

 and the ship fills with the wind upon the starboard side, as seen at d, 

 and she is now on the starboard tack. It is at times a perilous evolu- 

 tion, and if there be much sea on is found impracticable. To insure 

 success however under ordinary circumstances, the helmsman just 



frequently caused by the helmsman neglecting to shift the helm when 

 the ship acquires stern-way. When, from having lost all velocity, she 

 will neither stay nor fall off, she is said to be " jammed up in the 

 wind," or " in irons," the remedy being to brace the head-yards aback 

 and " pay off." If such happen when too near shore the danger is 

 imminent. (VEERING.) 



END OF VOLUME VII. 



DRADBURV ANtl F.VAXS, PRINTERS, WBirEFMiRS. 



