254 



HARBOUR CONSTRUCTION. 



suspended, will hang at the required inclination (Fig. 66, p. 251). 

 Sometimes long tapered lewises are used instead of T-headed 

 bars; but blocks are liable to be split by them, and they are 

 therefore not desirable. 



Large washers and nuts have in some instances been built 

 into blocks, the lifting bars being screwed into them for lifting. 



FIG. 71. 



FIG. 72.' 



FIG. 74. 



FIG. 75. 



FIG. 77. ' 



Block-lifting appliances. 



and unscrewed and withdrawn when the blocks have been set. 

 This plan has several drawbacks, not the least of which is that 

 all the washers and nuts are lost, as they cannot be got out of 

 the blocks. 



Some other block-lifting appliances are illustrated in Figs. 

 72-78. 



1 Min. Proc. Inst. C.E., vol. cxiii. part iii. 



