MATERIALS. 145 



the present time. The pier at Milton-on-Thames, below Graves- 

 end, designed and carried out by him in 1842-44, was supported 

 on cast-iron columns 3 feet in diameter, the metal being \\ inch 

 thick, and these were unaffected by such action. The Gravesend 

 town pier, by the late Mr. Tierney Clark, M. Inst. C.E., was on 

 similar supports, the metal being \\ inch thick; and these too, 

 though about thirty years old, were similarly unaffected. The 

 cast-iron columns of the Maplin Sand lighthouse, erected about 

 the same time, likewise remained sound, although the metal was 

 only | inch thick. 1 



Min. Proc. Imt. C.E., vol. xxviii. pp. 228-230. 



