DEVONSHIRE. This fine county is rich in minerals available in the manufacturing arts. Slate rocks are very predominant. These rocks are quarried for roofing-slates : IP they are metalliferous, affording iron-stone, and veins of tin, copper, and lead : theyeins or lodes which yield tin or copper, run, as in Cornwall, from N. E. to S. W. (approaching more or less to E. and W.), and those which afford lead run nearly at right angles to these. The strata in the mining field about Tavistock which yields tin, copper, lead, and manganese, are traversed by porphyritic (elven) beds, bearing nearly east and west. A few lead and copper mines are wrought in North Devon : the lead is combined with silver. The lime stone is quarried for building and burnt for manure : beautifully veined marble is worked in different places. Imperfect coal or lignite, called Bovey coal, occurs at Bovey Heathfield, on the right or south west bank of the West Teign or Bovey river in a plain where the strata of it rise to the surface. It lies in pa rallel seams from four to sixteen feet thick, at six or eight feet distance from each other, to the depth of sixty feet, and exhibits a grada tion from the most perfect ligneous texture to a substance nearly approaching the character of pit coal. Potters' clay and pipe clay are found in the same neighbourhood. The Bovey coal is used for fuel in the potteries on Bovey heath, and by the poorer people of the neigh bourhood : but its difficult and imperfect com bustion, and fetid gas, render it unfit for do mestic use. The Dartmoor granite is remark able for the size of the felspar crystals which it contains: it is much valued for its durability, fineness of texture, and the size of the blocks : it is quarried and exported to a considerable extent, especially to London. It is metallife rous; containing veins of tin, even the rock itself being sometimes impregnated with this metal.
Grass laud being far more abundant in De vonshire than arable, butter, cheese, and live stock may be considered as the chief agricul tural produce for exportation. The clouted
or clotted cream of Devonshire is a well-known delicacy ; it is made by heating the milk on the hearth, or by means of a stove, to a de gree a little below the boiling point, when the clouted cream ries to the top like a thick scum, and is taken off when cooled. This cream being merely stirred briskly with the hand or a stick, is converted into butter. The chief beverage of the Devonshire people is cider, which is here superior to any other in Eng land. The soil on the slopes of the hills is peculiarly adapted to the growth of fruit trees, especially on a loose rocky bottom, where the roots may insinuate themselves and find mois ture at all times. The wood grown in Devon shire is chiefly oak, but beech, ash, and elder are interspersed, according to the soil and si situation.
A few towns are briefly noticed in separate articles ; such as EXETER, CREDITON, Hem-. TON, &c. We may here state that at Prince Town,on Dartmoor, is a building which was for merly a prism], but which has lately been leased to a coh.pany who were engaged in extracting naptha from peat. Considerable interest is just now attached to this place from its being the field of an important experiment on the application of convict labour. In the autumn of 1850, a number of convicts were sent down here to be employed in the reclamation of a portion of the moor and other useful works. The prison is of such extent, and so well con structed, as to afford abundance of room, se curity, and facility of supervision, and the situation, though bleak and dreary, is very healthy, while it is sufficiently removed from any populous neighbourhood, thus permitting the experiment to be made under very favour able conditions. At present the number of convicts at Dartmoor is limited, but it is un derstood that it will be increased if the experi ment succeeds.
Mining, quarrying, and lace-making are the chief industrial pursuits of Devonshire. Speci mens from many of the chief towns will be displayed at the Great Exhibition.