482 
THE GEOLOGIST. 
TNrimy otlicv antiquaries follow llie old and rxitloded notion of these so-called 
dihivial gravels having' been solely formed by the aetion of water. This is an 
error, for water has been only the motive ])ower in their distribution. Beyond 
this, all it has effected has been by its continued frictional action in the partial 
roundine; by abrasion of the sharp angadar edges of those more or less triangular 
fragments into which flints naUirally break hy the action of frost or by per- 
cussion. Whole beds of shattered flints arc of frequent occurrence in chalk, 
and the mere waste and destruction of the strata would liberate hcajjs of frag- 
ments with angular edges as sharp as those of a flint freshly broken by the 
hammer. The knocking action of one pebble dashed against another could not 
]n-oduce the triangular pieces we have alluded to, but would cover the sur- 
face with iimumerable pits, due to the natural conchoidal fracture of the chips 
broken out. 
M. de Perthes next details the researches made by himself, Dr. Rigolet, and 
others m the neighbourhoods of Abbeville and Amiens, some accounts of which 
were, from time to time, laid before the " Societe d'Emulation" of Abbeville, 
and " Societe dcs Autiquaii'cs de Picardie," and published in theii' respective 
transactions. 
(To he continued.) 
BRITISH ASSOCIATIOJT MEETING. 
( Continued from pcye 444 ). 
Queries on Slickensibes submitted to the President of the Geolo- 
gical Section, Aberdeen Meeting, September, 1859, by Mr. J. Price, of 
Birkenhead, with Replies to the Queries by Professor D. T. Ansted. 
I offered the following remarks to the Section, under a conviction that 
individual and local observation of small facts could never, as such, be 
out of place at the meetings of an association so eminently Baconian 
as that then assembled at Aberdeen ; and that this must ever be the 
province of the majority of naturalists — to provide instances for the few master 
minds to generalize. I mean to include under the name " Slickensides" eveij 
mhieral surface which, apart from crystallization, exhibits an cxtraordhiary 
degree of polish. And as I beheve this phenomenon has never yet received 
anything approacliing to a satisfactory explanation, I wsh to call the attention 
of practical geologists to the subject, and induce them to look out for it in sec- 
tions (whether natural or artificial) of every rock-formation. I am acquainted 
with the fact in situ only in the neighbourhood of Birkenliead (New Red), par- 
ticularly the celebrated Labyrintliodon quarries at Storeton, where it is very 
well Ulustrated, and in the "mountain-limestone" at Llysfaen and Bryn 
Euryn, near Abergele, North Wales. But I believe I have met with hand 
specimens of it (generally ballast) in granite, serpentine, coal, coal-shale, and 
trap, near Shrewsbury. I presume " specidar" galena, antimony, &c., to be the 
