15 to Mining Purposes

15 ON THE PROGRESSIVE APPLICATION OF MACHINERY TO MINING PURPOSES. BY MR. THOMAS J~HNTAYLOR, OF EARSDON,NEWCASTLE-ON-TYNE. % In the following paper an attempt is made to trace the progressive application of Machinery to Mining purposes ; more especially to the drainage of mines and raising of .coal in the Newcastle coal district : a subject which must, it is conceived, prove interesting both to the mining and mechanical engineer, as involving not only one of the earliest employments of the steam engine, but also the first extensive use if not the invention of railways. The inclined position of beds of coal is intimately connected with the mechanical means required for working and draining them. In some cases the beds rise or crop out to the surface or “day,” as it is called ; and in others they are buried with the associated strata at considerable depths below. As these strata rise from depths of 100, 200, 300 fathoms and upwards, along an inclined plane, broken by faults and interruptions, but still ultimately making their way out to the day, it is ob~ousthat depth is a principal element in the consideration of the mechanical means required for working and draining the coal beds. In the “shoaler” &es, or those worked near the surface, the lifting of water, which is undoubtedly the miner’s greatest enemy, is comparatively easy : so also is the raising of the coal to the surface : and, it may be added, the ventilation ; for inflammable gas is hardly ever met with in mines worked near the day, though carbonic acid gas, Imown to miners as “ stithe ” or choke damp, is abundant in such mines. There are thus three distinct requirements for all mines,- drainage, raising of the coal, and ventilation ; but their nature and extent vary in different portions of a coalfield, and hence beiome characteristic of particular epochs. By the old miner, the ‘6 old man ” as he is callled, who cannot be accused of any want of shrewdness in Downloaded from pme.sagepub.com at Monash University on June 5, 2016 16 MINING MACHINERY. comprehending his position, the shallow mines were easily worked, and drained by adits, many of the coal beds being found above the natural drainage levels of the country : in a middle period, when deeper mines were to be worked, a perpetual struggle arose for the necessary mechanical powers, a struggle resulting in many contrivances, some of which were, as will be seen, very ingenious : and thirdly, we arrive at the epoch of the steam engine, which has ever sirice continued to be the right arm of mining operations, and has also led to many other mechanical appliances as a natural consequence of the development it has given to mining. Early period of CoaZ Mining.-The earliest and simplest plan of coal mining was that of a day drift or adit, along which both water and coals were brought, as shown in the diagram, Fig. 1, Plate 1 : the coals were carried in the workings by men or boys, first by hand or on their backs, and afterwards, as an improved step, on sledges which were trailed along the ‘‘ thill ” or floor. The shafts sunk on the continuation of the forward workings supplied what ventilation was supposed to be needed, and were surmounted by the common winch or jack-roll worked by hand. The mode of conveyance from the pit was on the backs of horses or donkeys, which carried what is st,ill called a ‘<load” in some outlying districts : the pack-horse load, weighing about 24 cwts., being the same in fact as the “ coal boll,” of which it is the origin j and the name carries us back to that not very remote period when there were neither railroads nor even accessible carriage roads for purposes of transit. The early period of active coal mining in England extends from the twelfth to the beginning of the seventeenth century. There are many curious notices of coal in these times : amongst which may be mentioned that in the fourteenth century coals were sent from Newcastle to be used in sharpening the tools of the workmen employed in building Windsor Castle ; coals having been made use of for smiths’ and manufacturing purposes long before they werc introduced for domestic consumption. TO the latest portion of this period, namely the commencement of the seventeenth century, may be referred the employment of horses in drawing coals and water by whim gins : by Downloaded from pme.sagepub.com at Monash University on June 5, 2016 NIINING JIACHINERY. 17 this substitution of horses for manual labour an additional power was gained. But the coal beds were becoming so rapidly exhausted near the outcrops that in the year 1610 Sir George Selby declared in his place in parliament, for the grave consideration of the legislature, that the Newcaktle coalfield would be worked out in a period of 21 years. To us, who continue to raise, two centuries and a half after his time, 16 millions of tons yearly from this coalfield, such a statement appears remarkable enough ; but the speaker alluded, it must be supposed, to the working out of the accessible portions of the coalfield, and his observation denotes the near approach of a period when it would be necessary to win the deeper coal : an object which, however desirable, there were at that time absolutely no known means of accomplishing. With a view fully to appreciate the nature of the difficulties which the early mining adventurers had to encounter in regard to drainage, it may here be mentioned that, as a general rule, a greater weight of water than of coal is raised to the surface in the mines of Northumber- land and Durham. In particular cases, such as that of Wylam Colliery and Percy Main Colliery near Newcastle, the weight of water raised has been nearly 30 times that of coal : in other cases 7 or 8 times the weight of coal. To very deep mines, especially when the top feeders have been stopped back by cast iron caissons or tubbing, this remark does not apply : but still, as a general and average result, a greater weight of water than of coal is required to be raised, without taking into account those cases in which water is found to excess, as in the half-indurated marly sand beneath the niagnesian limestone of the county of Durham. Middle period of Coal Hining.-In the middle period of coal mining, or during the whole of the seventeenth and commencement of the eighteenth century, there was a perpetual struggle to obtain some mechanical power which might prove adequate to win and work the mines lying to the deep. In the absence of this power attempts were made to stop back the top feeders by caissons or " tubbing" as it was called. The first attempt of this kind is mentioned by William Waller, in his account of the mines of Sir Carbcrp Price, 1698. In R Downloaded from pme.sagepub.com at Monash University on June 5, 2016 18 MININO MACHINERY. the preface to this work he ascribes to Sir Humphrey Mackworth the credit of applying, at his mines in Glamorganshire, “ a new method of coffering out the water from his shafts and sinking pits, and thereby preventing the charges of water engines, and also recovering a large vein of coal by that means, which was in vain attempted by other artists.” In the ‘* Complete Collier,” published in 1708, is a description of “the stopping back of shaft feeders with wooden frames ; ’’ and the author (name unknown) also says that he has heard of “ iron frames that have been used at Harraton in Durham, made square and deeper than the thickness of the quicksand, to put back these quicksands, which may be of good use, though they must be dear.” It was not however until 1795 that cast iron tubbing came much into vogiie : in that year Mr. Barnes employed it at Walker Colliery near Newcastle, the pieces consisting of entire circular rims the size of the shaft. In 1796 Mr. Buddle adopted the more convenient plan of segments, at first connected together by screw bolts, but afterwards by wedging the joints, each segment constituting in fact the voussoir of a circular arch. By this means very large water feeders are dammed back, giving in some cases a pressure of 300 to 500 feet head of water. In reference to the introduction of machinery, the u Complete Collier” (1708) furnishes a clear view of the state of mining at that time : it states, ‘‘ in some places we draw water by water, with water wheels or long axle-trees, but there is not that convenience of water everywhere.” The long axle-trees referred to worked chain pumps, as shown in the old sketch Fig. 2, Plate 1 : an endless chain turned upon a large axle, having attached to it a number of oblong wooden buckets or troughs, which filled at the bottom of the pit and discharged at the top as they turned over the great axle-tree. When there was sufficient water for working the wheel, the full complement of buckets was placed upon the chains j but as the water decreased, a proportionate number of alternate buckets were detached, for the purpose of regu- lating this rude machine according to the power available. None of the buckets were more than half full at the time of discharging at the top, owing to the leakage and the vibration of the chains, the water continually pouring down the pit like a deluge.

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