serves the same thickness throughout its whole extent. Instances to the CHAP. 2. `contrary sometimes occur, in which the same bed will become narrower or Coal. wider, and sometimes be divided by a stratum of incombustible earthy matter, in different parts of its course. Few beds of coal are worked at a great depth which are less than two feet in thickness. The stratum lying over a bed of coal is called the roof, and the stratum under it the floor. The facility of getting coal depends very much on the compactness of the stone which forms the roof, not only on account of the security from falling, but for keeping out the upper water and preserving the pit in a dry state. The great expense incurred in supporting the roof when it, is loose, frequently prevents a valuable bed of coal from being worked, or absorbs all the profit. In some situations the roof is indurated clay, impregnated with bitumen and pyrites. When this falls down, and is intermixt with water and small coal at the bottom, it takes fire spontaneously; on which account the miners close up the space with common clay, where the coal has been worked, to prevent the access of air to the combustible matter."

The uppermost floor of all coal-measures is either an indurated clay, which has various appellations, or a peculiar kind of stone called crowstone or ganister, which generally belongs to the second and third coal shales, This crowstone is considered an important stratum, as it abounds in large and curious vegetable impressions, and as it is useful in road making, and very serviceable for making crucibles.-The slines, or length-way joints, which naturally divide the coal seams, vertically range for the most part in such a manner that the coals face the two o'clock sun; and it is observed by the colliers that these natural joints in the coal are not affected in their direction, by the dip, however rapid or easy; nor is it influenced by the tendency of the dip to any other point of the compass, nor is it checked or diverted by the faults. These curious facts (as Mr. Farey observes) seem to prove, that the kind of crystallization which broke the coal seams into their regular rhomboidal pieces, was completed prior to the faults and dislocations of the strata.-The whole extent of coal-measures in Derbyshire amounts to about 190,000 acres.

A list of COLLIERIES, which are or have been in work in Derbyshire.

(formerly)

Adelphi (or Duckmanton) furnace, E of Calow, | Barlow-common, 4m. W of the town, 8th coal
near Long Duckmanton, 12th coal (an iron
furnace and mines)
Aldercar (Ouler-car) near Langley-mill in
Heanor (formerly)

Alderwasley, NW of the village, 14 m. E of
Wirksworth, 1st coal

Alfreton, S and SW of the town (formerly)
Alfreton furnace. See Somercoles
Alton, S of the village, 14 m. E NE of Ashover,
3rd coal, crowstone, brasses
Ankerbold near Tupton, m. NW of North
Winfield, 9th coal (formerly)
Arbor-lands, 1 m. SSW of Eckington, 9th coal
(formerly)

Apperknowl common, E of Dronfield, 9th coal
(lately)

Ash-gate in Brampton, 2m. W of Chesterfield, 7th coal (formerly)

Aspinshaw, W of Hayfield in Glossop, 2nd coal Bank, SE of the village, 14 m. SW of Holmsfield, 5th coal (formerly)

Barlborough-common, W of the town (former

ly)

Baslow, lin. E of the town, 2nd coal, brasses
Beeley moor, at S end of Chatsworth old park,
1m. NE of Beeley, 1st coal (formerly) crow-

stone

Beighton-field, E SE of Barlborough (formerly)
Belper-gutter, m. E of Belper, 2nd coal (for-
merly)

Belper lane.end, 1 m. NW of Belper, 1st coal,
brasses

Belper town, NW of the church, 1st coal (for-
merly)

Bent, near White Moor, 1m. NE of Belper,
2nd coal (formerly)

Benty-field, m. E of Codnor, smithey coal
Berley-moor, N of the village, 22 m. W of
Beighton, 10th coal

Berrisford-moor, W of Tupton (near Winger-
worth furnace)m. NW of North Winfield,
9th coal (formerly)

Berristow, 1 m. ENE of South Normanton
(lately)

Biggin, 1 m. N NE of Tibshelf (formerly)

List of
Collieries.

Bole Hill, SE of the houses, 14 m. SW of Eck-Gleedless-common, E and NE of the village, in ington, 8th coal (formerly)

History and

mode of working.

Thick wood, NW of Ouler Bar, 12 m. W NW of
Holmsfield, in Dronfield, 2nd coal [formerly]
Tibshelf, one-third m. S of the church
Ticknall, at SW end of the town [formerly]
Tor-mine, one-third m. SW of New Mills, in
Glossop, 2nd coal [formerly]

Town-field, 1m. NW of Heage, 1st coal [for-
merly]

Wigwell, NE of the houses, 14 m. E NE of
Wirksworth, 1st coal [formerly]

Wildens-mill, two-thirds m. WNW of Brim-
mington, 8th coal

Wilders-green, NW of the houses, 14 m. W of
Barlow, 7th coal [formerly]
Wingerworth-furnace, N of Woodthorp, 3 m.
S of Chesterfield, 7th coal [formerly] an iron
furnace and mines

Wingerworth-park, NW of the hall, 2 m. S of
Chesterfield, 9th coal

Troway, S of the village, 24 m. E SE of Ecking-Wooden-box, E of Swadlingcote, 13 m. SE of ton, 8th coal, smithy coal

Tupton-green, 1 m. NW of North Winfield, 9th
coal

Water-field, E of Stanton, 14 m. WSW of New-
hall [lately]

Westfield [or Sough] one-third m. SW of Bark
borough [formerly]
West-Hallam [or Ferneyford] near Lewcote-
gate, 1 m. NE of West-Hallam
West-Hallam windmill-hill, m. NW of the
town, and also one-third m. E of it [formerly]
Wheat-croft, in Crich, NW of the village, 1st
coal [formerly]

White-holly-coppy, S of the houses, 13 m. S of
Ticknall (formerly]

Whittington-moor, two-thirds m SE of the
church, 10th coal

Newhall [lately]

Wood-field [or Park-gate] one-third m. N of
Newhall [formerly]

Woodhouse [or Stubley] m. SW of the vil-
lage, 14 m. W of Dronfield, 8th coal
Woodhouse-lane, m. SW of Smalley church
[formerly]

Wood-nook, 14 m. W NW of Sutton, in Scars-
dale, 9th coal [formerly]

Woodthorp, W of Tupton, 14m. WNW of
North Winfield, 7th and 8th coals [formerly]
Woodthorp, N of the houses, 14 m. E of Stave-
ley, 12th coal [formerly]
Woodwards-close, S of Swadlingcote, 1 m. NE
of Church Gresley

The discovery of coal in Derbyshire, or indeed in any part of England, and the use of it as fuel cannot accurately be traced to any particular period. There are reasons however to believe that it was partially known and consumed in the earliest era of our history. At Ashby Wolds, and other places where the coal measures basset through the red marl, there have been found rude ancient tools of flint, which apparently belonged to the aborigines of the island. In the west riding of Yorkshire there are still vestiges of beds of cinders, and in one of these Roman coins have been found. The Barwell colliery, a few miles westward of Newcastle-uponTyne, bears evidence of its having been worked by the Romans. But coal was not held in estimation as fuel even so late as the fourteenth century; for the burning of coal was prohibited in London in the year 1308 by the proclamation of Edward the First. In the reign of Queen Elizabeth, the burning of coal was again prohibited in London during the sitting of parliament, lest the health of the knights of the shires should suffer during their residence in the metropolis. It appears however, from a charter of Edward II. dated 1315, that the coal of this county was in use, and that the lord of Alfreton, Thomas de Chaworth, granted to the monks of Beauchief, permission to supply themselves from his domains of Norton and Alfreton.

The old coal pits or workings were upon the edge or basset, where the strata appeared immediately under the vegetable soil or thin alluvial covering. These were afterwards followed, until (as the colliers express it) the mineral had got cover under the yellow limestone, grit or other upper stratum; and there the beds or measures, whether coal or other mineral, are always more valuable than near their bassets, in the open works or shallow pits, to which the getting of coals seems to have been long confined. When coal became an article of general consumption, about the beginning of the seventeenth century, great researches were made for the discovery of that important mineral, and some superstitious practices necessarily were resorted to, in the then general deficiency of geological information. At

present, men have become conversant with those natural indications which direct them with tolerable certainty to the treasures hidden beneath the surface of the earth. The disruptions or faults, the vertical position of deranged and isolated strata, and other consequences of the violence to which the coats of the globe have been subjected, will occasionally induce difficulties and errors, but an acquaintance with each individual stratum, and its relation to the known coal seams, is the best, if not the only true method of discovering other coal seams, and of successfully opening and conducting collieries or coal pits.*

Coals, as well as other minerals, are obtained from pits or mines, by means of pumping-shafts, soughs or levels, which will be more particularly described in speaking of the lead mines of this county. Sinkers or shaftsmen are persons who from their youth acquire a practical knowledge of the strata in their neighbourhood, as far as regards their order and thickness. In the process of their labour, the sinkers endeavour to ascertain what beds of compact rock, coal, &c. will stand without lining, while where the shaft is carried through soft or crumbling measures, a curb or flat ring of sound oak or elm is laid on the bottom, on which stones or bricks are built to the top. The sinking is then carried on within this ring or curb as far as is judged safe, when a new curb is laid, and the wall of the shaft is supported by a pier built up from it. Where deep valleys intersect a mineral district, tunnels, soughs or water-levels have been made as the means of relieving or laying dry the mineral veins or the seams of coal. The use of steam-engines has rendered these levels less necessary, but there are some in this county which will be hereafter mentioned, and which are well worthy the attention of the traveller, on account of the skill, labour and perseverance that have been employed in their construction.

By means of a sough or level driven across the measures so as to reach

From the inclination or bending of coal strata, they always rise near to the surface in some parts of their course, and would be visible if not covered by soil or gravel. In the intersections formed by rivulets, or by accidental fractures on the sides of hills in a district, the nature of the strata may often be determined, and should be ascertained before any expense be incurred in boring or sinking for coal. When this is done, a proper station should be chosen; which requires great judgment: otherwise it is possible to bore or sink to great depths, and miss a bed of coal which exists very near the place: this will be evident from the inspection of the two stations, a and b, (Geolog. plate, compartm. D) in the latter it would be impossible to meet with the bed of coal, c, because the search is made beyond the line where it rises to the surface, or, in the miner's language, crops out. At a, coal would be found after sinking only a few yards. In most situations, it is better to search for coal as deep as can be done without expensive machinery, by sinking a well in preference to boring. By sinking, a decisive knowledge of the nature and thickness of the strata can be ascertained as far as you descend, which can only be imperfectly known by boring; for the latter mode is liable to great uncertainty of result, from bendings or slips of the strata. If, for instance, the borer be worked in the situation a, (Geolog. plate, compartm. D) it will pass through a great depth of coal, which in reality may not be more than a few inches in thickness. Besides the uncertainty of the results, the grossest impositions are sometimes practised to answer interested purposes, and induce proprietors to continue the search, where there is no reasonable probability of success. Where coal strata come to the surface, they are generally in a soft decomposed state, and intermixed with earthy matter. They frequently present no appearance of coal, but the soil may be observed of a darker colour. The real quality of the coal cannot be ascertained until it is found below in its natural undecomposed state, lying between two regular strata of stone, or indurated clay. In general it is observed that the same bed improves in quality, as it sinks deeper into the earth. Coal strata are generally split or divisible into rhomboidal blocks, by vertical joints, which range about E SE and W NW: these are called slines; the oblique shorter joints are called cutters. There is more than one-third of England in which all search for valuable coal is useless: the knowledge of a negative fact becomes important, when it saves us from loss of time, expense, and disappointment.

CHAP. 2.

History and

mode of

working.