Obfervations on the Flints of Chalk-beds. 309 
V... Balls of ochre are fometimes found in chalk- 
pits. Thefe balls, on examination, clearly appear 
to have exifted in fome other ftate fince their depo- 
fition in the chalk-beds. ‘They contain lumps of 
matter, much refembling ferrugineous vitrifications: 
whence I conjecture, that the whole ball was once in 
the fame ftate. : 
Long fince this conjecture was formed, I obferved 
in the quarries about Clifton, appearances which 
ftrongly confirm it. I have before me brecciated 
* ferrugineous maffes, and. mafles of friable ochre, 
each having precifely the fame ftructure. I have 
even a feries of fpecimens, from the hardeft, reddifh, 
brown ferrugineous breccia, to the moft friable ochre, 
in which the angular fragments are feen perfeély; and, 
what feems to remove all doubt, you can perceive 
fpecks of ochre, beginning to form here and there 
in the hardeft of thefe maffes.—All the compact 
ferrugineous maffes, which I have feen about Clif- 
ton, are varieties of hematites. J add, as.a circum- 
ftace which feems to point out the origin of thefe 
maffes, that a Gentleman one day laft {ummer picked 
up in my prefence, in a quarry between Gloucefter 
Row and the Mall, a fpecimen of hematites, which 
has exadtly the fhape of a drop, falling from one 
contiguous furface to another. To that, which may 
be fuppofed the upper furface, it is attached by a 
harrow neck; while the body, a little flattened by 
reafon 
