INDEX. 
113 
Page. 
Moisture, modes oi determining 32-37 
Molybdenum, distribution of 18,82 
determination of 82-84 
precipitation of, by hydrogen sul- 
phide 81 (footnote) 
qualitative test for 84 
Nepheline, detection of 108-109 
Neubauer, Eugo, cited 64,65,66 
Nickel, determination of G1-G2 
Nitrogen, estimation of. 107-108 
Oven for water determination, description 
and figure of 37 
Penfield, s. L., cited 42 
methods of water determination used 
by 38-4 1 
mode of determining specific gravity 
recommended by 29 
Penfield and Genth, cited on precipitation of 
aluminum, iron, etc., by ammonia. 55 
Penfield and Harper, cited on washing of 
precipitated alumina 55 
Penfield and Minor, cited 104 
Penfield and Sperry, cited 107 (footnote) 
Phosphoric and titanic oxides, combined 
a verage of, in rocks of earth's crust. 17 
in alumina precipitate, peculiar occur- 
rence of 57 (footnote) 
Phosphorus, determination of 78-79 
Pirsson, L. V., arrangement of analyses pro- 
posed by 22 
cited on detection of nepheline 108 
Platinum, presenceof, in filtrates from silica 54 
removal of, from filtrates... 54, 57 (footnote) 
Platinum crucibles, loss in weight of, on 
blasting 53 (footnote) 
Potassium bisulphate, cautions concerning 
mode of preparation of 25 
Pratt, J. H., modification in method for de- 
termining ferrous iron devised by. . 94 
l'r. cht,H., cited 99 (footnote) 
Pyei lometer method of determining specific 
gra vity, description of 29-30 
Pyrite, determinations of ferrous iron as 
affected by 94-95 
Qualitative analyses, unadvisability of 26 
Radiator for evaporation, description of . . . 23 
figure of 24 
Ramsay, William, cited 107 
Ransome and Hillebrand, cited 88 (footnote) 
Reagents, quality of 25-26 
Ridsdale, C. H., cited 58, 85 
Riggs, R. B., development of Gooch amyl- 
alcohol method of separating alka- 
lies from magnesium by 101 
Rose, H., cited 59 (footnote), 107 
method of estimating fluorine devised 
by 103-105 
Rosenbladt, T., method of estimating 
boron devised by 107 
Sandberger, F., cited 21,107,110 
Schmoeger, M. , cited 66 
Silica, method of separating alumina, etc., 
from 47-54 
mode of drying and testing 52-53 
modes of determining 47-54 
recovery from alumina precipitate of 
amounts of 56-57 
Bull. 176 8 
Page. 
Silica, separation of, in rocks containing 
fluorine 47,50 (footnote), 103 
soluble, estimation of 109-110 
Silicates, modes of decomposition of 48-49 
Silvestri, , cited 107 
Smith, J. Lawrence, figure showing cruci- 
ble for alkali determinations de- 
vised by 97 
method of determining alkalies devised 
by 96-99 
Sodium carbonate, limit of impurity of 25,51 
Sodium carbonate method for decompi »s Lng 
silicates, description of 50-52 
Sonstadt, E. , cited 99 ( footnote ) 
Specific gravity, modes of determining 28-31 
Sperry and Penfield, cited 107 (footnote) 
Stokes, H. N., acknowledgments to 110 
cited 76, 89, 95 
Stokes and Hillebrand, cited 90 (footnote) 
Streit and Franz, method of separating zir- 
conium devised by 76-77 
Strontium, determination of 62-64 
percentage of rock content of 17-18 
separation of barium from 63-64 
separation of calcium from 63 
Sulphides, determinations of ferrous iron 
as affected by 94-95 
methods of distinguishing 105 
nearly constant presence of, in rocks. . . 18-19 
Sulphur, determination of 105-106 
Tantalum, rare occurrence of 21 
Thorium, determination of 77 
rare occurrence of 21 
Titanic and phosphoric oxides, combined 
average of, in rocks of earth's crust. 17 
in alumina precipitate, peculiar occur- 
rence of 57 ( footnote) 
Titanium, estimation of 67-73 
loss of, by evaporation with hydrofluoric 
acid alone 69 ( footnote) 
preliminary procedure when material 
is scanty 79 
solubility in caustic alkalies of oxide of. 60 
Tongs for handling crucibles, description 
and figure of 23 
Ulbricht,R., cited 66 
Ullmann, C, cited 91 (footnote) 
Uranium, determination of 77 
Vanadium, condition of 88 
determination of 82-88 
determinations of ferrous iron as af- 
fected by 94, 95, 96 
distribution of 82 
effect of, in estimation of total iron .... 58 
occurrence of 18 
precipitation of, with iron, etc 58 
preliminary procedure when material 
is scanty 79 
qualitative tests for 84-85 
tables showing results of tests for 86, 87 
Vogt.J.H.L., cited 89 
Washington, H.S., arrangement of analyses 
advocated by 22 
Water, methods of determining 32-17 
Water determination, drying oven for 37 
drying temperatures in 33 
figures of Jannasch's glass tubes for — 46 
