TRANSACTIONS OF THE SECTIONS. 143 



at one time, and that only during the operation of fixing the new columns and 

 cutting out the old ones. 



The first thing to be done was therefore to prepare the new columns with 

 projecting brackets (as shown in sketch), of sufficient lengtli to reach beyond the 

 ends of the wall beam h (fig. 2), so as to support the ends of the middle one after the 

 old columns were removed. As it was impossible, however, to remove that part 

 of the column which went through the beams, it was necessary fii'st to fix the 

 new columns under the wall beams in the line d, and subsequently to cut out the 

 old ones at c progressively, as the work advanced from one end of the room 

 to the other. The bi-ackets on the new columns were made to project to about 

 the same extent on both sides ; but as the)' could not be extended the whole length 

 on the side next the original colunms, until the latter had been cut out and removed, 

 the bracket intended for supporting the end of the middle beam at c was left 12 

 inches short, so as to leave sufficient space for attaching the appar.atus for cutting 

 out the old column ; and a loose end was afterwards bolted to the bracket, and made 

 to fit the stump end of the old column after it had been neatly cut off and removed 

 as shown in sketch at c. 



The carrying out of this work was ably accomplished by the contractor, Mr. 

 Andrew Ker ; and in order to save time and labour, an apparatus was devised by 

 him to talie advantage of the shafts in motion, and thus to cut out the columns with 

 great rapidity and success. The apparatus itself consists of two cast-iron clips 

 embracing the column, and fomiing a table for supporting a spur-wheel, which 

 revolves roimd the colunm and cames a steel cutter. The wheel is driven by a 

 worm-shaft and pulley, which received motion from one of the driving-shafts in 

 each room. The shank of the cutter is screwed to receive the rachet, and by means 

 of a finger or peg the cutter receives the required advance, equivalent to the thickness 

 of the cut every time the rachet passes the finger. 



By this means the old colunms were quickly cut out and removed, and the 

 loose end of the bracket having been inserted, with two strong bolts, the end of 

 the middle beam was thus supported with the same security as if the original 

 columns had never been disturbed. 



Improvement in Pontoon Trains. By G. Fawctts, North Shields. 

 A complete pontoon train has been arranged to go either way or turn on its 

 centre, vrith all the detailed fittings made reversible and interchangeable. This 

 is a combination of a light and strong waggon-frame, with traversing frames 

 between the wheels, where the beams and planks for forming the platform of a 

 bridge are packed in separate compartments for simxdtaneous handling, and are 

 secured there by a novel system of bolting, the load thus strengthening the 

 carriage and increasing its stability. Above these frames the required number of 

 inverted boats are packed.^See ' British Association Eeport of Transactions of 

 Sections,' 1863, pp. 172, 173, article " Waggons and Boats" (Newcastle). In form- 

 ing a bridge, the rowlocks on both gunwales form a double support for the beams, 

 which are scarphed and keyed together with bolts and forelocks. The bolts are of 

 an elliptical section, and fit into oblong holes and plates forming a rigid jointing. 



On Locomotive Engines and Carriages on the Central Rail System for working 

 Steep Gradients and Sharp Curves, as employed on the Mont Cenis. Bu 

 J. B. Fell. ^ 



It appeared that this work is proceeding most satisfactorily, and that it will pro- 

 bably be completed by the end of the year, and will be opened about May next. 

 When this is done, the line of rail will be mibroken between Paris and Brindisi, 

 on the Adriatic, from which port the Italian Government are nmning a line of 

 steamers to Alexandria. Should our Government adopt this route for our Indian 

 mails, as it is expected will be the case, instead of that of Marseilles, a savinw of 

 something l^ke forty hours will be effected in their transmission between Lomlon 

 and Alexandria. The works at Mont Cenis could be executed for £1000 per mile 

 for the railway, and £250 per mile for permanent way ; the stations would amount 

 to another £1000 per mile, the rolling stock amounting to £750 per mile, the total 



