3-U) 
BULLETIN OF THE NATURAL HISTORY SOCIETY. 
in Dark lake cave and elsewhere. Crystalline calcite or 
carbonate of lime has been found in seams of the limestone rocks 
in several forms of crystals. 
Asbestus has been found in the magnesian rocks that accom- 
pany the upper limestones of Lily lake. 
Other minerals that occur in the park are Epidote, a grass- 
green mineral, found on jointed surfaces and in veins of the 
granitic rocks; Tourmaline, which occurs in quartz veins of the 
schists further eastward, may be looked for in the schistose rocks 
of the park; Zircon has been found in microscopic crystals 
in the granitic rocks of the park; Hyacinth, is a translucent 
variety of the same mineral. Quartz, occurs in prismatic crystals 
in the quartz veins, etc.; Feldspar, \n tabular crystals, as a 
constituent of the granitic rocks; Hornblende, as a common 
mineral of the syenitic rocks. 
Rocks. — Besides the limestones which are noticeable at 
many points in the park, there are hills and ridges of Syenite, 
or quartz-diorite, that are prominent in the northern half of the 
park; the highest hill in the park, on its western margin, is of 
rock of this kind. Another hard rock which forms the ridge 
on the northwest side of Lily lake, and becomes more prominent 
at the Look-out hill is Quartzite, or metamorphic sandstone. 
The southern ridge in the park overlooking the “Valley” and 
the “Marsh” is composed of ancient volcanic rocks, with 
scoriaceous (amygdaloidal) and fragmentary beds (braccias) 
at the base, and finer (volcanic ash) beds higher up; the whole 
mass is now so thoroughly compacted and hardened as to form 
a prominent ridge rising higher than the limestones of Lily lake, 
etc., to the north of the Valley deposits on the southern margin 
of the park. 
The limestone l)eds are numerous and show much variety 
of composition, some purely calcareous, others highly magnesian, 
others with so much disseminated carbonaceous or graphitic 
matter as to have a dark “blue” or gray color. 
A study of the topography of the park will show how inti- 
mately its physical features are connected with the nature of 
the rocks which underlie its hills and valleys, and rise in many 
places to the surface. 
