THE CABLE SHIP ON REPAIRS. 



215 



In the latest design by this firm a large cast-iron sleeve slides 

 on the cylinder, and to this sleeve the sheave is attached, and 

 also the two side rods which carry a crosshead some distance 

 above (see Fig. 125). To the crosshead is attached a piston 

 rod with piston working on the inside of the steel cylinder, 

 which is filled with oil, and, the piston being a loose fit, this acts 

 as a dash-pot to steady the movement. The top of the steel 

 cylinder Is, of course, fitted with a packed gland. 



On repairing-steamers it has been usual to provide two 

 dynamometers, one forward for grappling and picking-up indi- 



FiG. 126. 



eating up to a maximum of 25 tons, and the other aft for paying- 

 out and indicating up to about 5 tons. As paying-out in repair 

 work is now done almost entirely from the bows, two dynamo- 

 meters are provided forward, besides the one aft. The grapnel 

 rope passes over one of the bow sheaves, over a loose guide 

 pulley, under the forward dynamometer sheave, over another 

 guide pulley, and then has three or four turns round the picking- 

 up drum attached to a shaft driven by a steam engine. The 

 drum is held by a powerful brake while grappling, and the ship, 

 which is crawling over the ground at not more than 10 to 15 

 fathoms a minute, is stopped immediately a steady strain on the 



