PT. III.] SUMMARY. 193 



not too large, well adapted for castings. In the manufacture of bar 



iron, however, the presence of phosphorus is injurious, as it renders 



the iron " cold short." 



The effect of sulphur is very different. It renders the pig iron 



viscid, and much impairs the quality of castings, 

 Sulphur. „ .-. _ , 



making them liable to contain naws and air- 



bubbles. For the manufacture of bar iron, pig iron containing much 



sulphur cannot be employed, as the resulting metal is " red short" to 



an extent which renders it perfectly useless. 



The principal objection therefore to the use of Kaniganj coal, 

 whether for sea-going steamers or for the manufacture of iron, is the 

 same, viz. the presence of iron pyrites. The opinion has already 

 been put forward above, that there are some seams in the Raniganj 

 field sufficiently free from this impurity to be available for both pur- 

 poses. The attention of coal proprietors in the field may however 

 well be directed to the importance of this point. 



The iron ores of the country have been largely collected during the 



progress of the survey. They have already been 

 Iron Ores. 



described with reference to their mode of occur- 

 rence, abundance, &c. (See ante pp. 74-77.) They comprise, however, 



besides the clay iron ores, some very rich deposits 

 Magnetic Iron. 



of magnetic iron, associated with metamorphic 



quartzite just beyond the south boundary of the field, near the 



village of Tituri, about 2 miles West of Beharinath Hill. The ore 



occurs interlaminated with the quartzite and gneiss in bands varying 



in thickness from 3 inches to 2 feet. They are very pure, and contain 



from 60 to 70 per cent of iron. 



The following list gives the percentage of iron 

 Clay Iron Ores. 



in several different varieties of clay iron ore 



from different spots on the Raniganj field.* 



* These assays were by Mr. Gr. E. Evans, late Curator of the Geological Museum, Calcutta. 



A 2 



