236 Messrs. Jackson.and Alger on the 
sie, excepting color. It is probably that mineral, colored by 
green earth. These masses often occupy the whole interior of 
the geodes, and are deeply indented by the pyramids of the 
surrounding quartz crystals ; whence we suppose it to have been 
of more recent formation, or at least of more recent induration, 
than the quartz enveloping it. Botryoidal cacholong also occurs, 
encrusting the interior of the vacant cavities of the quartz. This 
locality will. repay the mineralogical traveller for the trouble of 
a visit; and the course of the stream is a correct guide to the 
spot where specimens may be procured. 
The only place which we have not already described, worthy 
of a visit from the geologist, is that part of Digby Neck where 
the North mountain range is interrupted by the Gut of Annapolis. 
This is two miles from the town of Digby. At this place, is situ- 
ated the Light-house, which serves to guide navigators to the 
entrance of Annapolis Basin, the most capacious and secure 
harbour for large vessels in Nova Scotia, and one in which, as is 
observed by an historian of the country, a thousand ships may 
ride, secure from every wind. 
The site of the Light-house is on a projecting rock of colum- 
nar trap of the most compact variety ; and the numerous irregular 
crevices have been filled with chalcedony, jasper, and agate, 
which, adhering firmly to the contiguous rock, give it additional 
firmness, enabling it to resist successfully the fury of the waves, 
which, in boisterous weather, dash completely over the precipice, 
and wash from its surface every trace of soil or vegetation. The 
centres of the columns of trap appear to be more readily acted 
upon by the sea, than the parts contiguous to the chalcedonic 
veins, and thus concavities are produced, in which the spray from 
the sea, slowly evaporating, leaves crystals of its saline contents, 
as in natural salt-pans. 
