KXAMI'U.S 01 STKF.L BINS. 



317 



by a system of shafting and gears. There is an opening in the side of the drum, and when the 

 drum is revolved this opening comes opposite the opening in the bottom of the bin and the drum 

 is filled. The drum is then revolved and the material is dumped into the larries. 



Circular Bins. Circular bins are made of both steel and reinforced concrete. A circular 

 ore bin with a hemispherical bottom is shown in Fig. 13 and Fig. 14. 



EXAMPLES OF BINS. Steel Coal Bin for Rapid Transit Subway. A cross-section of a 

 I,ooo-ton suspension bunker built by the Rapid Transit Subway, New York City, is shown in 

 Fin. 15 and Fig. 16. The bunker is supported on posts and is covered by corrugated steel. The 

 bin is lined with a layer of concrete 3$ in. thick, reinforced with expanded metal. The details of 

 construction are plainly shown in the cuts. 



Plan of Hoppers and 

 Hopper Bottoms 



\General Elemti'on ofHopptrs Botfoms 





S8n 



I 



^ W' 4> '"4 ' Faces Co/3 -~* 



* Sectional Elevation at 'M' 

 FIG. 17. HOPPER BIN CANANEA CONSOLIDATED COPPER Co., CANANEA, MEXICO. 



