72 SEVENTH REPORT—1837. 
clay slate, the lamine of which are slightly contorted. In one place 
the slate was traversed by a wide vein of greenstone porphyry, in which 
the crystals of felspar were large. The abrupt southern termination 
of Montserrat, in this defile, shows the slate immediately covered by 
a reddish sandstone, containing rounded nodules of quartz, and some- 
times fragments of the clay slate. The upper portions assume more 
and more the appearance of the conglomerate already described. The 
enormous mass of Montserrat is composed of these rocks, which pro- 
bably belong to the greywacke formation. In proceeding to Barce- 
lona, the sandstone continues to be visible as far as St. Andreu and 
Papiol, where it forms low cliffs; but in the fine plain of Barcelona, 
the rocks are covered by a rich clay marl, only broken near the sea by 
a sandstone, containing turritelle and turbines, and forming the hill of 
Monjuic, which is crowned by the strong fortress of that name. 
In the author’s excursion to Cardona, he passed the northern ridge 
of Montserrat; which, instead of forming, as usually represented, an 
isolated mountain, should rather be considered as the termination of a 
chain, the general direction of which is from N.N.E. to 8.S.W. The 
shattered spires of the Caval de Bermat are formed of the same far- 
cilite, which extends as far as the dangerous defile at Bremita de San 
Jayme. Here it is succeeded by strata of sandstone flag, which the 
author traced beyond the city of Manresa, to the eastern side of the 
Rio Cardonero; but the western bank of that river exhibited strata of 
a dull grey limestone. As the traveller approaches Cardona, these rocks 
are concealed by a vast bed of reddish, marly clay ; and, in ascending 
to the city of Cardona from the Cardonero, he is surprised to find, 
instead of rocks projecting from the soil, grey masses of salt of great 
purity. 
Reine to his more detailed description of the salt-mine of Car- 
dona in the Geological Transactions, the author illustrated his short 
account by a drawing of this celebrated mine. The salt presents a 
nearly mural precipice of about 400 feet high, of a greyish white 
colour, having its surface channeled by the rains into numberless 
smooth hollows with sharp edges. The body of the salt is so pure, 
that to convert it into the whitest culinary salt, it is merely ground in 
mills. This remarkable deposit has been described as a mountain of 
salt; but this the author considers as incorrect; it rather seems to be 
a valley filled up with that mineral. The nearest visible rocks, on 
both hands, incline towards the salt valley; the hills on both sides of 
it are higher than the bed of salt; and the whole is covered by a 
stratum of plastic clay, which defends the salt from wasting by the 
elements. This mine is a royal appanage, rigidly guarded by sentinels 
stationed on the adjacent heights, who have orders to fire on all who 
enter the mine without authority; a circumstance which renders 
caution necessary in those who examine it. There were only one 
hundred miners employed in 1814, the period of the author's visit to 
Cardona, who were under the direction of ten subordinate officers, 
and a general superintendent. The miners earned two pecetas (about 
two shillings) a day ; they work from six A.M. to seven P.M., with the 
