152 
INDEX. 
''age. 
Moyer (J. S.) & Co., quarry of, views of 78 
slate quarries of 76,78,124 
Midler, F. E., on concretions 33 
Muscovite in slates, generation of 7, 13 
occurrence of 12,14 
N. 
National Red Slate Co., slate of 16, 74, 95 
National Slate Co., slate quarry of 53 
New Jersey, slate deposits of 70 
slate of, production of 126-131 
New York, slate deposits of. location of 70-71 
slate deposits of, location of, map show- 
ing 88 
sections across, plate showing 90 
slate ( »f, analyses of 36, 41-42, 71, 73, 74 
characteristics of 71, 124-125 
composition of 39-42, 72-74 
descriptions of 72-74 
faults in 29 
geology of 7, Tii 
prices of 125 
production <>l" 126-131 
structure of 10, 19,22,44 
veins in 32 
slate quarries in, diagrams of 92,96 
structure at 72 
Nodules, occurrence ami character of 33 
North Bangor, Pa., slate quarry at 77 
North Bangor Slate Co., slate quarry of — 77 
North Blanchard, Me., slate quarries a ... •'>■">, 124 
Northfield, Vt., slate quarrii sat 90-93, 124 
structure at, figure showing 91 
Norton, L. M., analysis by 63 
O. 
Old Bangor quarry. Set Mover, J.S., A: Co. 
Olenellus, occurence of 94, 98 
Olive grits, occurrence of 98, 100 
Ordovician time, crustal movements in 34 
slate depositsof 71,95-110,119 
Ottrelite in slate, occurrence of 11 
P. 
Paleozoic shales, analyses of 37 
Pawlet, Vt., section at 98-99 
section at, plate showing 20 
shear zone at, plate showing 30 
Peach Bottom region, Md.-Pa., slate depos- 
its of , description of 85-88 
slate deposits of, location of 85 
slate of, analyses of 34-35 
characteristics of K6-88, 124-125 
composition of 12-13 
geology of 6, 85-86 
prices of 125 
section of, figure showing 87 
watte of 42 
w eathering of 37 
Ten Argyl, Pa., slate quarries at 78-80, 124-125 
weathering at 80 
Pennsylvania, geology of slate regions of.. 75-76 
Lehigh County, slate deposits of 81-85 
slate deposits of, analyses of 84 
Northampton County, slate deposits of. 76-81 
slate deposits of, location of 75, 85 
Page. 
Pennsylvania, slateof, analyses of. 34-36, 38, 84, 88 
slate of, characteristics of 75-76, 
84,86-88,122,124-125 
cleavage in 24 
composition of 12-13, 49 
geology of 6, 10, 34, 75, 81, 85-86 
joints in 28 
prices of 125 
production of 126-131 
structure in 19, 75, 76 
figures showing 82, 83 
weathering of 37, 39, 80-81 
slate quarries in, map of 80 
views of 82,84 
See also Peach Bottom region. 
Penrhyn, Wales, slates of 6 
Petrography of slates, history of 9-11 
minerals in, character of 11-13 
sizes of 13-14 
Pfaff, E., on rutile in slates 13 
Phillips, John, on cleavage 23-24 
Phillips and Sharpe, on slaty cleavage 23 
Phoenix, Ariz., slates from near 51 
Phyllite slates. See Mica slates. 
Pigeon slate, character of 88 
Pitts, A. L., slate quarry of 113-1 14,123-124 
Placerville, Cal., slate deposits near 56,8a 
slate district of, geologic map of 56 
Polarity of slate 27 
Porosity of slate 47-48 
Portland cement, slate waste used in man- 
ufacture of 60 
Potash-mica. See Muscovite. 
Poultney, Vt., shear zone at, plate showing. 30 
slate deposits at, bedding of, plate 
showing 20 
Prindle, L. M., on Vermont slates 97 
Production of slates, statistics of 125-13'i 
Prospecting, suggestions for 44-45 
Provident Slate Co., slate quarry of, struc- 
ture in, figure showing 8'^ 
Provo, Utah, slate deposits at 8S 
Purple slate, occurrence and character of. 107-10* 
Pyrite in slate, occurrence of 11, 109-1K 
Pyrophyllite in slate, occurrence of l; 
Pyrrhotite in slate, occurrence of..., 11 
Q. 
Quarries, slate, technical description of ... 
Quarrying, difficulties of 
Quartz in slates, occurrence of 11, 12, 14, 
plate showing quartz veins 
R. 
Raceville, N. Y., slate of | 
Renard, A. F., on petrography of slates. .11, 12, 2 
Reusch, H., on shear zones 2 
i Reverdin and dela Harpe, on slate porosity. 4 
Rhodochrosite, bed of, analysis of 7 
Ribbons, occurrence of 19,1 
removal of, view of 8 
Richardson, C. II., on Vermont slates 9 
Rising A Nelson Slate Co., slate quarry of.. 12 
Rock ma it formation, slate deposits in 5 
Rogers, II. D., on structure of slates 23,2 
Rogers, W. B., on Virginia slates 11 
