Only a short time since there was discovered in the Lower Coalmeasures at Idle, a magnificent specimen of Megalichthys Hibberti; and now, at Clayton, near Bradford, has been found one of the grandest examples yet seen of a fossil Sigillaria tree. It was in the Fall Top Quarry, at Clayton, worked by Messrs. Murgatroyd and Sons, that this remarkable fossil was discovered, and these gentlemen deserve the highest praise from all geologists for the skill and extreme care with which they have bared the fossil, and also for their kindness in allowing it to be inspected. This quarry is not far from the edge of a bold escarpment overlooking the Thornton Valley, and the well-known Elland Flagstone is worked here for landings, flags, etc. Between the Better-Bed-Coal and the Flagstone there is a great thickness of sandstones, shales, etc., of various characters, and it was in these measures that the fossil tree was discovered about 12 feet below the surface. The sandstones just referred to are of little commercial value, many being irregularly bedded, and others very perishable in their nature; the better kinds are used for rough walling, the remainder being merely rubbish to fill up other excavations. The marketable flagstone is at a considerable depth in this quarry, and blasting operations have to be carried on to remove rapidly the overlying strata. After one of these explosions, Messrs. Murgatroyd observed part of a large fossil tree exposed, and, profiting by their knowledge of geology (which, by the work of the Yorkshire Geological Society and also of the Leeds Geological Association, is rapidly spreading throughout the entire county), they immediately suspended further operations, and, instead, gave orders to their workmen to carefully bare the remainder of the roots.
Observation of Overlying Strata Failure Height in Fully Mechanized caving in Tongxin mine
