At the Leys ironworks, north-west of Brierley Hill, Mr. Firmstone sank a pit, as follows:—
| FT. | |
| To the bottom of the Thick coal | 492 |
| To ditto of Heathen ditto | 9 |
| To ditto of Stinking ditto | 10 |
| To ditto of New mine (?) | 24 |
| Beds of fire-clay, rock, binds, red and grey clod, and red rock, 1 foot to 7 feet each | 39 |
| Red sandstone grit full of pebbles | 38 |
| 612 |
Making a total of 120 feet below the Thick coal; having reached which depth the water burst in on them with such force and rapidity as to oblige them to abandon the sinking.
It is singular that in each of these pits, although at different depths, the lowest beds were red, clunch in one case, (which might be marl,) and sandstone in the other. One might speculate on some beds belonging to the Old red sandstone having come in, were it not that many of the true Coal-measures, both above and below the Thick coal, contain much red and mottled marl and clunch.
At Corbyns Hall Mr. Gibbons sank 172 feet below the Thick coal, the bottom beds being alternations of clunch and rock binds, when a quantity of salt water rushed in with such force as nearly to drown the mines.
At Shut End mines Mr. Foster sank 111 feet below the Thick coal, passing 16 feet below the representative of the Fire-clay coal, and found much of the water in the lower measures very salt.
The following is a complete abstract of the Graveyard Trial pits, south of Lower Gornal:—
| FT. | |
| To bottom of Thick coal | 43 |
| To„ bottom of„ Heathen do. | 15 |
| To„ bottom of„ Sulphur do. | 43 |
| To„ bottom of„ New mine do. | 24 |
| To„ bottom of„ Fire-clay | 8 |
| To„ bottom of„ Bottom | 40 |
| To bottom of another little coal passing through many beds of rock, &c. | 112 |
| Several beds of rock | 21 |
| 306 |
(See Vertical Sections, sheetnb18, No. 23, lower part.)
Making a total of 133 below the Bottom coal, or 263 feet below the Thick coal, without attaining the base of the true Coal-measures.
For ascertaining the exact thickness of Coal-measures between any known bed and the top of the Silurian formation in any part of the field, we have but scanty data in the pit sections. Even where it is certain, or highly probable, that the sinking was continued down into the Silurian rocks, we are often left to guess at the place of the exact boundary between the two formations, since the miners are but little
