282 NATURE NOTES. 
GEOLOGICAL NOTES. 
In one of the intrusive dykes east of Elie, Fife, a peculiar 
specimen of drusy quartz was obtained. The crystals are 
black in colour, and much modified in form, and it was only 
after a close examination that a small typical crystal of 
quartz was observed. On trimming the specimen, pieces of 
bituminous matter were found scattered through the vesicles 
of the rock. These, on heating, intumesce, and finally burst 
into flame, burning with a smoky yellow light. The crystals 
seem to owe their black appearance to this, for on strongly 
igniting a powdered sample, the colour was destroyed and a 
dirty grey residue remained. 
A similar occurrence of bituminous matter with crystals 
of quartz was observed in a small geode found on the south- 
eastern slope of Carnethy, above Penicuik, in a dyke built 
up largely of blocks of andeside obtained from two small 
quarries situated close at hand, In this case, however, the 
crystals were perfectly clear and transparent, showing both 
prism and pyramid faces, their ends being embedded in a 
piece of bituminous matter (asphaltum) about the size of a 
bean. 
The evidence in the last case points to the bituminous 
matter occurring as a secondary product, and most likely 
from hot or cold solutions, not from a gaseous state, as the 
necessary heat would have destroyed the crystals. In the 
Elie specimen, either the two substances were formed 
together (the peculiar character of the quartz might be due 
to this), or the quartz has been deposited last. 
R. DYKES. 
Some very fair pseudomorphs of Hematite after pyrites 
may be found on the north side of Duddingston Loch, at 
the junction between the intrusive mass of the Long Row 
and the sandstones on the east side of the cliff dipping into 
the waters of the loch. The crystals vary from less than a 
quarter of an inch square to more than one inch square, and 
retain the sharp outline of the original pyrites. 
