VITRIFIED TILE SILOS. 



101 



cut many of the details of construction. A represents a block 

 with curved recess at top and bottom for reinforcing rods and 



a flange on each side of the block 

 so that the bulk of the mortar 

 is confined in the wide groove 

 and only a very narrow strip 

 exposed. B calls attention to 

 the mitred groove at top and 

 bottom for reinforcing rods to 

 form a lock joint. The narrow 

 apertures on each side of block 

 form a tongue-and-groove mor- 

 tar joint when laid in the wall. 

 C and D illustrate the door jamb 

 and regular blocks of another 

 type. It will be noticed that 

 B gives plenty of room on top 

 for mortar and reinforcement. 

 Still another type of silo is indi- 

 cated by the blocks E, F, G, H 

 and I. E and F are door jamb 

 blocks. G is a glazed floor or 

 paving block. H and I show 

 two views of the regular wall 

 block. J illustrates the cast iron 

 door sill and K indicates the 



Fig. 43. — Group of Patented Clay Blocks of various manu- 

 facturers. 



