IRON POSTS, 
1 13 
subject to; they generally cost three times as much as wooden 
posts of the same strength, but they certainly last more than 
three times as long. 
All the Egyptian lines are made with Siemens’ posts, and 
it may be seen from fig. 47 that, notwithstanding their 
strength, the lines constructed with iron posts are not without 
elegance. 
‘ Fig. 4 7. —Siemens, Halske & Co.’s Posts. 
In Australia, a post with a cast-iron pyramid at the base is 
much used. It is made by Oppenheimer of Manchester, and 
is represented in figs. 48 and 49. Its base has the shape of an 
inverted pyramid with sharp edges, and it can be forced into 
the ground by means of a pile-driver mounted on a tripod 
(fig. 49); p p\ are two simple pulleys round which pass the 
ropes r r f , having the handles h h ', attached to them. The 
