132 lie-inforced Concrete for Farm and Estate Purposes. 



Blocks, the required thickness of the wall, are placed on the 

 ground, and each side of the mould is placed against them ; 

 ties of flat bar iron, one bent round as a hook, and the other 

 end pxtnched with holes, are passed through slots in the boards 

 level with the bottom angle iron, and a pin is put in the most 

 suitable hole, and a wedge driven in at the hook end against 

 the angle iron. Distance pieces are dropped into place in the 

 top of the mould, and iron ties, both ends hooked, are slipped 

 over the angle iron and wedged up. The re-inforcement being 

 in position, the mould can be filled in the way described for 

 the columns. When the length of wall is completed the 

 mould is placed on top of the previously made wall and 

 grips it 6 in. deep, resting on the bottom ties, the distance 

 blocks at the bottom being required no longer ; but each course 

 is now only 18 in. deep instead of 2 ft., as was the bottom 

 one. As the wall increases in height, staging must be erected 

 to work on, and in ordinary methods of erecting concrete 

 structures scaffolding is employed. Mr. Hopkins' method is 

 a very simple one, consisting of pairs of brackets bolted back 

 to back on either side of the wall by means of a single bolt 

 through the wall ; it is then only necessary to lay planks on 

 these to make a staging to work on. When a course is com- 

 pleted the brackets are moved upwards, the holes left in the 

 wall being grouted up with cement. 



It is important that the concrete should be mixed almost 

 dry, and it is rammed into the moulds until it is thoroughly 

 consolidated and quite hard. The forms are then removed 

 immediately, and the surface of the concrete is rubbed down 

 until it is smooth, thus obviating any rendering with cement. 

 Great stress is laid on the ramming, in fact the concrete should 

 be so hard when the forms are taken off that it can hardly be 

 scratched by a knife. All superfluous moisture is squeezed out 

 to the surface, and the rubbing-down process removes the marks 

 of the boards entirely. As the piers, or columns, are moulded 

 in situ thei-e is no difficulty in providing for doors and windows. 

 Bolts and eyes for hinges, &c., are put in as required while the 

 concrete is still " green," and the heads and sills of windows 

 are set in the walls as the latter are built up. As regards the 

 roof construction, Mr. Hopkins employs concrete principals 

 supported by the columns in the external walls, and by partition 

 walls carried up at the apex of the roof. The principals are 

 spaced about 10 ft. apart. Flat pieces of iron are set in their 

 upper surfaces and support the purlins (Fig. 8) ; these carry 

 the roof boarding to which the " Eternit " slates are nailed. 



The details of the construction of this cowshed are as 

 follows : — The foundations for the columns consist of blocks 

 2 ft. 6 in. square by 1 ft. deep, re-inforced by a network of bars 



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