Frazer.l -iVO [Dec. 4> 



tween Centreville and Castle Fin in York county, not far to the north-west- 

 ward of the Peach-Bottom district. 



Note 2. Peach-Bottom slates. Mr. Andrew S. McCreath gave the fol- 

 lowing report of a specimen of the Peach-Bottom slate taken from J. 

 Humphrey & Co.'s quarry half a mile east of Delta, York county (p. 270, 



CCC). 



P. c. 



Silicic oxide (Si0 2 ) 55.880 



Titanic oxide (TiO„) 1.270 



Sulphuric oxide (Si0 3 ) » 0.022 



Alumina (A1 2 3 ) 21.849 



Ferrous oxide (FeO) 9.033 



Manganous oxide (MnO) 0.586 



Cohaltous oxide (CoO) (trace) 



Lime (CaO) 0. 155 



Magnesia (MgO) 1.495 



Soda (Na 2 0) 0.460 



Potash (K 2 0) 3.640 



*Carbon (CO) 1.794 



Water (H 2 0) 3. 385 



Iron bisulphide (FeS 2 ) 0.051 



lotal 99.800 



Note 3. The following analysis of two different kinds of ore from York 

 county are given. The first is from the " Lower Auroral," or limestone 

 schists. It is from Earley & Killinger's Mine two miles and one-half east 

 by north of Littlestown. It was analyzed by Mr. McCreath (See C, p. 44). 



P. C. 



Insoluble residue 12.320 



Iron sesqui oxide (Fe 2 3 ) 67.000 



Alumina (A1 2 3 ) 0.950 



Manganese sesqui-oxide (Mn 2 3 ) .. 2.341 



Phosphoric oxide (P 2 5 ) 2.804 



Sulphuric oxide (S0 3 ) 0.277 



Lime (CaO) 1.680 



Magnesia (MgO) 0.591 



Water (H 2 Oj 11.890 



Sum 99.853 



In the above there were 



Metallic Iron 46.900 



" Manganese 0.815 



Sulphur 0. 1 10 



Phosphorus , 1.224 



* Average of three determinations. 



