CHAPTER X. 



Slipways Advantages and Disadvantages Inclination of Ways Methods of con- 

 structing Foundations Slipways of ordinary construction Mode of working 

 Slipways to accommodate more than one Vessel Hydraulic Hauling Gear 

 Wire-rope Haulage Stress in hauling Resistance on sliding Slipways 

 Broadside Slipways. 



A SLIP is an arrangement by which ships can be hauled up on 

 shore, clear of the water, by mechanical means. 



Choice may be made between two systems. In one, a car or 

 cradle, moving on a number of rollers or wheels, is employed, 

 and in the other a sledge, running on well-greased ways, is 

 used. In the first, the friction to be overcome is a rolling one, 

 and in the second a sliding one. 



The first of these systems is the one generally adopted, and 

 has many advantages. The machinery, hauling appliances, arid 

 cradle may be lighter, and the wear of the working surfaces 

 is less. 



The selection of a slipway in preference to a dry dock will 

 depend upon many considerations, amongst which may be 

 mentioned the size of ships to be lifted, physical characteristics 

 of the site, cost, nature of the strata, direction and strength of 

 currents. 



A slipway consists of a foundation, the nature of which will 

 depend upon the special conditions appertaining to the locality. 

 A platform or roadway, generally of timber, to carry the sliding 

 ways or the rails. A carriage or cradle provided with sledge- 

 runners, or with wheels or rollers, and with an arrangement of 

 movable bilge-blocks for supporting the vessel ; and, lastly, the 

 hauling machinery whereby the ship is hauled above the water 

 level. 



Some of the advantages attaching to a slipway \vhcu 

 required for ships of moderate tonnage are that the first cost is 

 comparatively small. When hauled up, a ship can be readily 



