in 1666-but it is conjectured that it was practised much antecedent to that time, and it has continued in use, until recently, in Swedish and Danish ships. This mode of protecting the piles of harbours and piers from the ravages of the worm, is then treated of, and examples are given of its success in various situations. The third division treats of the inner coating or sheathing, which it has been found necessary to use, independently of the external metallic sheathing. It is stated, that some of the stronger and more adhesive kinds of inner sheathing, have proved mainly ⚫ instrumental in preserving vessels from sinking, when the outer sheathing has failed or been destroyed. Hair is noticed as among the earliest materials used for inner sheathing; it was usually applied in a loose state, and fixed by pitch or other resinous substances; it was subsequently woven into and used as a cloth ;—the coarse part of flax was in the time of the Romans bruised and driven between the seams of their galleys. A vessel was discovered in the Mediterranean Sea (between the years 1458 and 1464) in a depth of water of twelve fathoms, where it is supposed to have lain for nearly 1400 years; the deck and sides were covered with paper, linen, and leaded plates. In all the oldest vessels which have been discovered, the hair was perfectly fresh, although the timber was in a state of decay, and it is stated that the worm never penetrates through an inner sheathing of hair. In the year 1761, when copper sheathing was introduced, experiments were tried upon different kinds of paper for lining, and after trying white-lead and other substances, thick brown paper dipped in tar was found to be the best. A list is then given of the patents for different kinds of "felt" now used for inner sheathing, noticing particularly that of Messrs. Borrodaile and Co., which appears to be that which is most generally approved. Cocoa-nut fibre and cork, and many other substances, which have been tried at different times, are noticed, and the paper concludes with a copious list of the experiments upon the subject, which the author has compiled from various sources. "On the Sinking and Tubbing, or Coffering of Pits, as practised in the Coal Districts of the North of England." By Robert Thomas Atkinson, M. Inst. C. E. This communication describes the means usually adopted in the Northern coal districts, for effecting the "winning" of those valuable mines; and the author expresses the obligation he is under to his uncle, Mr. Buddle, to whose valuable documents he had free access during the progress of his labours. It commences with noticing the early periods of mining, before the introduction of steam power for pumping, when the extraction of coal was almost wholly confined to such tracts as could be drained by free water-courses, "adits," or levels; the chain and bucket pumps, and other limited and expensive means, are then explained, with the principles of free drainage, shewing that it was generally only applicable to districts of small extent, and that the best mines were left untouched. Steam-engines, upon Newcomen's principle, were first used in the Newcastle district in the beginning of the last century, and they underwent many modifications, before they were superseded by the Boulton and Watt engines, now generally used. The consequence of this introduction of steam power for raising coal, instead of accomplishing it by means of horse gins and other rude contrivances, is, that the capability of supply appears only limited by the demand. Over and above the weight of coal raised, it is necessary to draw immense quantities of water for the purpose of draining the mines. In some collieries the weight of water pumped up, amounts to as much as four times that of the coal raised. At the Percy Main colliery (which is rather an extreme instance), 3922 tons of water are pumped up daily, while only 636 tons of coal are raised in the same time. At the Benwell colliery, which is an average case, the weight of water amounts to 2020 tons per day, and the coals raised to 768 tons or 38 per cent. of the weight of water. The principal technical mining terms, in use in the northern districts, are then explained, and the author proceeds to describe the methods of sinking the shafts, noticing the difficulties which occur in traversing strata of various kinds, and the modes of overcoming them,-the temporary timbering with "cribs" and "deals" previous to walling-and the different kinds of " tubbing or coffering" of wood, stone, or cast-iron, used in passing wet portions of the strata or perishable rocks; this part of the subject is treated of very fully, with all the details of the construction of the different kinds, and the methods of using them. The cast-iron tubbing, which was first introduced by the late Mr. Buddle, is particularly noticed, as is also its use in segments at the Percy pit in the year 1779; some instances are given of the decomposition of cast-iron tubbing and pumps, when exposed to the smoke of underground furnaces and the action of mineral water, the combined action of which has been found to reduce the metal to the consistency of plumbago. The construction of the pumps, buckets, clacks, rods, &c. composing the apparatus for raising the water from the mines, is then fully described, with the "off-take joints" and the "fish-head" for drawing a drowned clack." The "hanging sets" or columns of pumps, with their "ground spears" used in sinking the shafts, are also described, with the method of fixing the cisterns at intervals in the shafts, for the different sets of pumps, which are all of the "lifting" kind. Accounts are then given of the sinking of Percy pit, Flatworth colliery, commenced in 1799-of Howden pit, Percy Main colliery, in 1804-and of a pit at the Barrow Field colliery, in 1822, in all of which, great difficulties were encountered. An explanation is then given of the extensive and complete set of sections of pits, drawings of the machinery, and of the models which accompanied the paper, and the author promises to extend the subject on a future occasion, as this communication is less comprehensive than was intended, and has been sent in its present state for the purpose of complying, during the session, with the usual condition of election. List of Disclaimers OF PARTS OF INVENTIONS AND Amendments MADE UNDER LORD BROUGHAM'S ACT. James Warren,-disclaimer and memorandum of alteration to patent dated 4th August, 1841, "for an improved machine for making screws." Filed 24th March, 1843. Dr. Henry Beaumont Leeson,-ditto to patent dated 1st June, 1842, for "improvements in the art of depositing and manufacturing metals and metal articles, by electro-galvanic agency, and in the apparatus connected therewith." Filed 25th March, 1843. VOL. XXII. 2 c List of Patents That have passed the Great Seal of IRELAND, from the 27th January, 1843, to the 15th of March, 1843, inclusive. To John George Bodmer, of Manchester, engineer, for certain improvements in the manufacture of metallic hoops and tyres for wheels, and in the method of affixing the same for use; and also improvements in the machinery or apparatus to be employed therein.-Sealed 27th January. James Clark, of Glasgow, power-loom manufacturer, for an improved mode of manufacturing certain descriptions of cloths. -Sealed 1st February. Thomas Thompson, of Coventry, in the county of Warwick, weaver and machinist, for certain improvements in weaving figured fabrics.-Sealed 18th February. Julian Edward Disbrowe Rodgers, of Upper Ebury-street, in the county of Middlesex, for certain improvements in the separation of sulphur from various mineral substances.- Sealed 18th February. William Young, of Queen-street, Cheapside, in the city of London, lamp-maker, for improvements in the construction of lamps and candlesticks.-Sealed 28th February. John Rand, of Howland-street, Fitzroy-square, in the county of Middlesex, artist, for improvements in making and closing metallic collapsable vessels.-Sealed 28th February. John Varley, of Colne, in the county of Lancaster, engineer, and Edmondson Varley, of the same place, cotton manufacturer, for certain improvements in steam-engines. - Sealed 15th March. List of Patents Granted for SCOTLAND, subsequent to February 22nd, 1843. To John Craig, of Stanhope-street, London, for certain improvements in machines or apparatus for weighing,-being a foreign communication.-Sealed 28th February. Edward Bell, of the College of Civil Engineers, Putney, Surrey, professor of practical mechanics, for improvements in applying heat in the manufacture of artificial fuel, which improve ments are applicable to the preparation of asphalte, and for other purposes.-Sealed 2nd March. George Bell, of the city of Dublin, merchant, for certain improved machines, which facilitate the drying of malt, corn, and seeds; also the bolting, dressing, and separating of flour, meal, and all other substances requiring to be sifted.-Sealed 2nd March. James Bullough, of Blackburn, overlooker, for certain improvements in the construction of looms for weaving.-Sealed 4th March. John Thomas Betts, of Smithfield Bars, London, for improvements in the manufacture of metal covers for bottles, and certain other vessels; and in the manufacture of sheet metal for such purposes,-being a foreign communication.-Sealed 7th March. Jules Le Jûne, of North-place, Regent's Park, London, engineer, for improvements in accelerating combustion, which improvements may be applied in place of the blowing machines now in .-Sealed 7th March. use. Thomas Howard, of Hyde, Cheshire, manufacturer, for certain improvements in machinery for preparing and spinning cotton, wool, flax, silk, and similar fibrous substances.-Sealed 11th March. Charles Payne, of South Lambeth, London, chemist, for improvements in preparing vegetable matters, where metallic and earthy solutions are employed.-Sealed 13th March. William Longmaid, of Plymouth, accountant, for improvements in treating ores and other minerals, and in obtaining various products therefrom; certain parts of which improvements are applicable to the manufacture of alkali.-Sealed 13th March. William Barker, of Manchester, millwright, for certain improvements in the construction of metallic pistons.-Sealed 16th March. Joseph Whitworth, of Manchester, engineer, for certain improvements in machinery or apparatus for cleaning roads; and which machinery is also applicable to other similar purposes.-Sealed 22nd March. In consequence of an error made in the Chancery Office, Edinburgh, the following Patents were omitted in a former List. John Thomas Betts, of Smithfield Bars, London, for improve ments in covering and stopping necks of bottles and other |