6 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. 
Glaze from slip. clay, 4, 55. 
Glaze on terra- cotta, 4, 54. 
Glenodinium, 2, 39. 
Gloeoporus, 3, 55, 61. 
Gloidium, 2, 12. 
Gomphidius, 3, 20, 51. 
Gonium, 2, 34. 
Gonostomum, 2, 24, 57. 
Grain of fire-clays. See Fine- 
ness of grain. 
Granby, 4, I5. 
Granite, 4, 17, 18, 69. 
Gravel deposits in lake basins, 
4, 23, 24, 26, 28, 70. 
Green bricks in kiln, 4, 83. 
Gregory, H. E., 1, 10, II, 4, 7. 
Grinding, effect of, on plastic- 
ity of clays, 4, 44, 45. 
required by china clays, 4, 
51. 
Grog, clay tempered with, 4, 46, 
75 76. 
Gromia, 2, 13. 
Gymnodinium, 2, 39. 
Gymnophrys, 2, II. 
Gypsum, composition of, 4, 40. 
plasticity of, 4, 45, 46. 
Hacking brick, 4, 82 
Hemotococcus, 2, 33. 
Halteria, 2, 57, 02. 
Halts of retreating glacier, 4, 23. 
Hanmer, C. C., 3, 5. 
Hardpan, 4, 12, 18. 
Hartford, brick-yards in vicinity 
of, 4, 77. 
clay at, 4, II, 25. - 
Heleopera, 2, 13. 
Heliozoa, 2, 11, 17. 
Hematite, composition of, 4, 31, 
40. 
mixed with clay, 4, 61. 
Hemidinium, 2, 39. 
Heteromastigoda, 2, 19, 29. 
Heteronema, 2, 30, 32. 
Heterophrys, 2, 17. 
Heterotricha, 2, 30, 53. 
Hexamitus, 2, 33, 36. 
Hirmidium, 2, 38. 
Histo, 2, 57, 60. 
Hobbs, W H., 4, 7. 
Hog-backs, 4, 19. 
Hollow brick, manufacture of, 4, 
79. 
Holophrya, 2, 40, 43. 
Holosticha, 2, 57, 60. 
Holotricha, 2, 39. 
Holyoke, Mass., 4, 11, 23, 25. 
Homogeneity of clay, 4, 41, 42, 
6: 
2. 
Hornblende, 4, 17, 31. 
Hudson Bay, source of conti- 
nental glacier near, 4, I9. 
Hyalosphenia, 2, 12. 
Hydnacee, 3, 67. 
key to the genera of, 3, 67. 
Hydnum, 3, 67, 68. 
Hydraulic method of mining, 4, 
71. 
Hydrous minerals, water in, 4, 
38. 
Hygrophorus, 3, 18, 34. 
Hygroscopic water in clay, 4, 37. 
Hymeniales, key to the families 
of, 3, 12. 
Hymeniales of Connecticut, 3. 
Hymenochete, 3, 70, 71. 
Hypholoma, 3, 19, 49. 
Hypochnacee, 3, 12, 75. 
Ice, stones carried by, 4, 28. 
stranded blocks of, 4, 23. 
Ice front, waters rising from, 4, 
24, 26. 
Ice sheet, advance and retreat 
of, 4, 23. 
final retreat of, 4, 28. 
readvance of, 4, 26. 
work of, 4, 19. 
Ilmenite, composition of, 4, 40. 
Impurities in clays, 4, 20, 31, 35, 
42, 47, 49, 50, 53, 61 
Included water in clay, 4, 43, 46. 
Interlocking character of clay 
particles, 4, 44. 
Iron, as fluxing agent in clay, 4, 
33. 
coloring effect of, neutral- 
ized by lime and mag- 
nesia, 4, 34. 
effect of, in brick clays, 4, 
54, 61, 65. 
in Glacial clays, 4, 29. 
in kaolin, 4, 29, 58. 
in refractory clay, 4, 35. 
in slip clay, 4, 55. 
in stoneware clays, 4, 52. 
in vitrifying clays, 4, 53. 
red oxide of, in rock resi- 
due, 4, 1 
Iron carbonate in clay, 4, 33. 
Iron compounds, influence of, 
on clay, 4, 31. 
Tron silicate in burned clay, 4, 
33. 
