242 ° 
MINERALOGY AND LITHOLOGY. 
List oF FicurEs. 
PuLaTeE I. (Frontispiece.) 
A fragment of a crystal of beryl from Grafton, with a scale representing its 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Pa 
10. 
dimensions in feet—page 67. . 
PLATE II. 
A thin section of a rock prepared for microscopic examination; natural 
size—page 7. 
Sections of an augite crystal, drawn to illustrate the optical deport- 
ment of biaxial crystals between crossed Nicol prisms. 2a and 23, 
sections in parallel light. 2¢, a section in light rendered convergent 
by the removal of the ocular from the microscope—page 15. 
Magnetite formed by the decomposition of a hornblende crystal, as 
seen in a section of diorite from a dyke near the Profile house— 
page 43- 
Magnetite as seen in sections of diabase. 4 and 4¢@ in diabase from 
Bemis brook, 44 and 4¢ from the flume in Lincoln, 4d from Con- 
cord, Vt.—page 42. 
Product resulting from the decomposition of titanic iron, as seen in a 
section of metamorphic diorite from Connecticut lake—pages 4o 
and 228. 
The same in a section of quartz diorite from Hanover—page 41. 
Titanic iron as seen in a section of diabase from Bethlehem. 
The base of a macled crystal of staurolite from Charlestown (Jackson). 
8a the base of one of these crystals as figured by Rosenbusch— 
page Ilo. 
Figure illustrating the arrangement of the crystalline axes with refer- 
ence to one another in the plates of muscovite and biotite, which 
are frequently found united together at their edges, in the mica 
quarries—pages 80 and 83. 
Tourmaline crystals flattened out between foliz of mica—page 85. 
PLATE III. 
Crystals of arsenopyrite from Franconia (Dana); 1 and 1 @ arsenopy- 
rite; 14 danaite—page 34. 
Crystal of vesuvianite from Amherst (Dana)—page 76. 
Crystal of tourmaline from Springfield, showing the peculiar habit of 
the species as there found—page I03. 
X 30 
X 50 
x35 
x 35 
x 50 
