Page:The Building News and Engineering Journal, Volume 22, 1872.djvu/529

 June 21, 1872. THE BUILDING NEWS. 507 The cost then per lineal yard of trench would be :— 8s, d Removing road and road-bed, 1 square yard.. 0 6 Excavation, 3 cubic yards, at 9d. ........... ate ey a Filling in and punning, say 23, at 5d. ... pemey 0) Carting away surplus earth, say },at1s.6d. .. 0 9 Restoring road and road-bed, 1square yard .. 0 6 @oxiper lineal yard >... cscewentevsucdastews «sehen 0 To which may be added any amount that may be desired for profit. Where the ground is such that the sides of the trench will not stand with the simple timbering here mentioned—that is, where veins of quicksand, wet clay, or other bad ground intervenes, poling boards have to be inserted behind the waling planks. These are generally slit battens, being 7in. wide, and iin. thick, or slabs of elm, cut to the length desired. Stable litter is very useful to pack between and behind the poling boards to keep back running sand, silt, or wet clay. In ex- tremely bad ground, nothing will do but close planking, consisting of Sin. deals, driven in the form of sheet piling behind the walings, and the joints regularly caulked with spun yarn. Such contingencies as these occurring on parts of the work, and the great amount of pumping sometimes required to keep the trench dry, make the cost of sewer excavations one of the most difficult things in the whole range of earthwork to estimate correctly, and the best way is to take a minimum cost in the manner we have here done, and add to it more or less, according to particular circum- stances. eg ee, BORING AND MORTISING MACHINE. E illustrate on page 508 a recently-introduced machine for cutting mortices and boring holes in chairs, tables, sofas, &c., which is supple- mented by another of similar construction for shaping the tenons and pins for the counterparts produced by the mortising and dowelling machine. It is patented by Messrs. M. and J. Pellock, of Beith, Ayrshire. The principle of the machine is as follows:—The part by which the mortice is cut consists of a revolving shaft fitted with bits, the diameter of which is equal to the width of the mortices desired. This shaft is carried in bearing blocks situated in a race, in which it is caused to reciprocate through a distance equivalent to the length of mortice required by means of a connecting- rod attached to a crank upon a revolving shaft near one end of the machine. This crank is preferably arranged with an adjustable throw, so that the range of the reciprocating spindle, and conse- quently that of the mortising bits, is capable of being adjusted to any required length of mortice. At opposite sides of the machine a table is situated, upon which a leg or other part of a chair or other piece of furniture is placed, and secured thereto by a cramp; the part wherein it is desired to make the mortice being brought in front of the bits, and being pressed against them by means of a screw, an accu- rately placed mortice is speedily formed, correspond- ing in width to the diameter of the boring bit and in length to the distance through which it moves. The part of the machine by which the dowel holes are bored consists of revolving bits, carried in brackets situated upon compound slides arranged upon the upper part of the framework, by means of which the bits can be brought into any position to suit the dimensions and nature of the piece of work or to the width of holes required to be bored, the bits being forced or drawn against the wood to be operated upon by hand levers, actuated by the attendant. The patentees prefer to make the machine duplex, so that two similar pieces of work may be operated upon simultaneously. In order to finish the joints of the work after it has been mortised and the dowel holes cut, the back legs andrail are put together by the tenons of the latter being entered into the mortices of the former, and cramped together in a machine for cutting the back joint ; this consists of two saws situated upon a transverse hollow shaft, through which a right and left hand screw passes, whereby the saws cam be adjusted to any distance apart corresponding to the length of the back rail of the chair, sofa, or other similar piece of work. The back is brought against the saws by a guide plate or slide set at right angles to the plane of action of the saws. This latter machine is also applicable to cutting and boring the dowel holes in back stays for chairs, having a com- pound boring apparatus attached thereto, the action of which is similar to that used for boring the dowel holes | in the legs of furniture, the bits being placed at the same distance apart, so that the dowel holes in both legs and back stay correspond; the same saws which cut the joints for the back also cut the ends of the back stay to bring them to the required length. Fig. 1 represents a front elevation of the mortising and dowel-hole boring machine, and Fig. 2 is a plan. As shown in Fig. 2 the part of the machine used for mortice-cutting is constructed with a revolving shaft A, the extremities of which are fitted with bits B, whose diameter is equal to the width of the mortice desired. This revolving shaft A is rotated at a high velocity by means of pulleys, and it is carried in bearing blocks situated in arace C. The shaft A and bits B are caused to reciprocate in the race C through the required distance by means of a connecting-rod D, attached to a crank on a revolving shaft carried in bearings supported by a bracket bolted to the framing of the machine. The erank is preferably constructed with an adjustable throw, so that the range of the reciprocating shaft A, and the mortising bits B, is capable of being set to any required length of mortice. The revolying shaft to which the crank is attached is driven by a belt passing over the pulley H. The tables I, upon which are shown in dotted lines the front and back leg of a chair about to be operated upon by the mortising bits B, are carried by brackets bolted to the framing of the machine, and are adjusted to the required height by means of screws and hand wheels, shown in Fig. 1, the screws being kept in position when adjusted by pinching screws. The tables I are situated upon horizontal slides, and by means of the screws and nuts placed under the tables are caused to travel to or from the mortising bits B by the operator turning handles affixed to the rods L (omitted here for want of room), in a right or left hand direction, similar to the manner of operating the slide-rest of a self- acting lathe. The legs or other parts of a chair or other piece of furniture, when placed upon the tables I, are secured thereto by the cramp K, which consists of a horizontal shaft furnished with a teather fitting into a corresponding groove in the eye at the head of the bracket O to allow of the position of the shaft being altered. At the end of each shaft a vertical screw is carried, furnished with a hand wheel, and upon tightening this the piece of furniture placed upon the table under it is firmly held in position, so that the parts wherein it is desired to cut the mortices being brought in front of the bits B, and being pressed against them by means of the screws worked by the handles on the rods L, accurately-situated mortices are speedily formed, corresponding in width to the diameter of the mor- tising bits B, and in length to the distance through which the bits travel in the race C. The portion of the machine by which the dowel holes are bored consists of revolving bits driven at a high velocity by means of the pulleys R, the bits being geared together in pairs or other numbers by means of spur pinions T, carried in brackets upon the hori- zontal compound slides M, which are carried and adjusted, as regards their height or level, by means of vertical screws passing through brackets bolted to the framing of the machine, and kept in position by pinching screws. The compound slides M are acted upon in one direction by the screws, the square heads of which are shown, and in a direction at right angles thereto by the hand levers, so that the boring bits can be brought into any position to suit the dimensions and nature of the piece of work about to be bored, the bits being pressed or drawn against the wood by an attendant actuating the hand levers. The sawing-machine which forms the complement to the one illustrated is constructed on the same principle, and with as little difference in the arrange- ment of details as the nature of its work will permit. All the parts, whether those for carrying the work or those bearing the tools, are adjustable one to the other to suit the difference in size of the various articles to be operated upon. —————— THE SCHOOL BOARDS. Lonpon.—At the ordinary weekly meeting held on Wednesday at Guildhall, the Chairman moved that Mr. Robson, the architect, be instructed to prepare plans for the proposed Board offices on the Thames Embankment. In submitting the motion the Chairman explained that under a special Act of Parliament the cost of these offices would be spread over a period of 50 years. He further added that the proposed offices would comprise a board- room for the Board meetings, architects’ and soli- citors’ departments, offices, and accommodation for the transaction of all the business of the Board, and ultimately perhaps a depot. Mr. Watson explained that the Board would not be in any way committed to the adoption of Mr. Robson’s plans when pre- pared, theinstruction to prepare them being distinctly given with that understanding. Several members spoke in favour of inviting competitive designs, and Dr. Barry, on the ground that by giving the instruc- tion the Board would, to a certain extent, be com- mitted to Mr. Robson as the architect of the proposed buildings, moved that the consideration of thematter be deferred for a week, which was agreed to. Norruampron.—A meeting of the Northampton School Board was held on Thursday week. The School Sites Committee presented their report, in which certain sites were recommended. The Board decided upon four sites, two in the west end of the town and one at the east end, the question as to the fourth site being deferred. SrapLenurst.—The tenders for the new schools at Staplehurst, to be erected from the designs of Pro- fessor T. Hayter Lewis, were delivered on the Ist inst., as reported in our issue of June 7. The ten- der of Mr. Budge, amounting to £4,200, has been accepted. A meeting of the inhabitants has since been held to induce the School Board to reconsider their decision, it being alleged that the proposed expenditure is exorbitant, and that the cost of a school for a town of 1,700 inhabitants should not exceed £2,000. ee ARCHITECTURAL & ARCHZOLOGICAL SOCIETIES. Lincotn DiocesAN ARCHITECTURAL SOCIETY.— The annual meeting of the members of this Society was recently held at Holbeach. The first day’s pro- ceedings commenced with divine service in Holbeach parish church, at the conclusion of which Edmund Sharpe, Esq., M.A., gave a description of the sacred edifice. On leaying the church the company proceeded in carriages to a piece of land near the railway station, which is supposed to be the site of an old burying ground, a quantity of human bones having been dug up there, and the bishop consecrated a memorial cross that has been erected to mark the spot. Thence they proceeded on an excursion to Whaplode, Fleet, Gedney, Long Sutton, Tydd 8. Mary, and Lutton, stopping at each place to inspect the churches, a description of which was given by Mr. Sharpe. Oxrorp ARcHITECTURAL AND HisrorrtcaL So- crery.—The concluding excursion this term took place on Saturday week. The party, about forty in number, left Oxford, and on arriving at Uffington proceeded to the church, where Mr. James Parker pointed out the chief features of the building, which he considered of the time of Henry III., and not earlier. It presented a very fine and complete speci- men church of that period. He laid special stress upon the importance of studying minutely the mouldings, which were to be seen in great perfection and great variety, and of which he exhibited different sectional diagrams which he had made. Mr. John H. Parker, C.B., who had just returned from Rome, joined the excursion, and said he considered that on the exterior changes had taken place respecting the windows, and he also called attention to some fea- tures peculiar to that church. The party then pro- ceeded, via the Dragon Hill, up to the White Horse ; mounting still higher, they reached the great British fortress. Here a meeting for business was held, after which Mr. James Parker gave a lecture on the British fortress, comparing it with other British fortresses in the neighbourhood, and those again with camps of the Roman type; next upon the Icknield Way, pointing out the evidences of its an- tiquity ; and, lastly, on the White Horse, respecting which he ventured to offer opinions very different to those put forth in Mr. Hughes’s “Scouring of the White Horse,” and ia the popular anti- quarian books of the last century. They then proceeded to Wayland Smith’s Cave, where Mr. James Parker again addressed the party. He read to them portions of the legend in its oldest form— viz., as it appeared in the Icelandic saga of the sixth century. Then passing from the romance, he pointed out that it was after all only an ordinary British cromlech. It had probably been covered with earth, and would therefore, perhaps, be called more pro- perly achambered barrow, the name of Wayland Smith having been applied to it probably through a blunder in determining the sites of a boundary attached to one of the Anglo-Saxon charters. The party then visited Hardwell Camp, and finally Wool- stone Church. —_——__@—__—_ It is stated that the two mura] paintings by the late Mr. Maclise, R.A., in the gallery of the new Houses of Parliament, are already exhibiting indica- tions of rapid decay. They represent the meeting of Wellington and Blucher at La Belle Alliance on the field of Waterloo; and the death of Nelson on board the Victory at the battle of Trafalgar.