134 
THE GEOLOGIST. 
friability, or softness. The upper beds are the well kno^ra and beautiful Purbeck 
marble ; beneath this, the thick beds of the harder kinds are adapted to sea-walls, 
fortifications, and other solid work, where minute cutting and nibbmg are not 
required. The more easily worked, or ' freestone beds,' are used for all kinds of 
architectural dressings, external and internal stone-fittings, sunk and rounded 
work, .such as sinks, troughs, gi-anary and rick-leg and ca])-stones, and in fact all 
those jmrposes where easy and clean cutting in work, and subsequent durability, 
are essential. The thin beds are employed for paving, and tlie stone when well 
selected is the best in the kingdom ; the very thni layers of tough limestone, or 
the tough fissile beds, are split into suitable thicknesses as tilestones for roofing. 
" All the useful beds are broken up by natural partings into blocks and slabs of 
various sizes, generally irregular rectangles, varying in size from ten or twelve 
feet long, by five to eight feet wide, down to eight or fifteen inches long, by six or 
ten inches wide, and three to eight inches thick. The latter class are termed 
pitchei's, the term ' horse pitchers ' being ai)phed to the larger sizes. It is worthy 
of remark, that amongst the useless beds, those called ^hones' by the workmen are 
the most frequent. The name is exceedingly appronriate, as both in the original 
mass, and in the smaller subdivisions, they have tlie smooth nibbed appearance 
of finished hones, or whetstones, as sold in shops. They are mostly argiUaceous 
or cherty limestones, in their original mass appearing perfectly solid, without 
any indication of partings, ljut on being handled continually subdivide into 
rhombic pieces. But the most interesting to the stranger is the great ' Cinder '-bed, 
a blackish or brownish rock, with two or three subdivisions, consisting almost 
wholly of a small oyster-shell, the Ostrea disloria, and so exceedingly hard and 
intractable as to be almost useless, and only operated on by blasting. It would, 
however, be very serviceable for marine works, or for exposed Ijatteries. 
" The principal ^Toups of beds of merchantable stone are termed veins by the 
quaniers. Dcscribmg them in descending order, we meet first wth the marble, for 
ornamental purposes ; then the marlle-ray for walls ; and the lane-end, or laneing 
vein beds, contannng good stone for tomb-stones, paving, waUing, and marine works. 
Below this is the freestone-vein, a grouj) containing kerb-, step-, and tUe-stone, and 
in its lower portion the admiratdy working and durable freestune, used for all kinds 
of cut and hollow work as above described. Below this, immediately above the 
freat ^ cinder'' -bed, is the downs-vein series, worked almost wholly for paving. 
>irectly under the cinder is the feather-vein series, worked for steps, walls, and 
marine works, then below this the new^ein beds supply still larger slabs and 
blocks, for similar puii)oses. 
" There is a freestone called Purbeck bur, exceedingly durable, yet veiy free to 
work, but the blocks are of small size. It was use<l for all the niasoniy of Corfe 
Castle, and the wondeifiil shaqjuess of the work there at the ])resent time, almost 
without sign of decay, shows the value of the material. The quames are not 
regularly worked, and are situated near Orchard, in Knowle parish. It belongs 
to the upper Purbeck strata. 
" The quames are all worked underground, and entered by oblique shafts, from 
twenty to a hundred feet deep ; a slope for dragging up the stone, and steps at 
the side for the workmen, wth a rude capstan worked by a horse at the top, and 
sheds adjoining, in which to carry on dressing the stone, constitute the whole 
an-angements in these primitive works. There are in the Isle of Purbeck about 
one hundred of these quames, more than half being in the immediate neigh- 
boiu-hood of Swanage ; it is difficult however to give the exact number, because 
there are constantly some being abandoned, or new ones opened. 
" Below the true Purbecks is a great mass of clay-, sand-, and marl-beds, which 
however thin out towards the sea-cliffs, so that there the Purbeck limestones rest 
at once on the crest of tlie true upper oolite, or Portland limestone, and it is to 
the stone obtained from this latter formation within the Purbeck district, that the 
name of ^ Purbeck^ -Portland is given. In the es.sential quaUties of closeness, 
slight alisoqjtion, and durability, it excels the true ' Portland,' but these qualities, 
characterising the oolite increasingly in an easterly direction, are also accompanied 
by increa.sed hardness, so that the fine quames of Tilly Whim, and Ilowcombe, 
near the eastern extremity of Purbeck, have been long disused for dressed and 
