272 



THE CIVIL ENGINEER AND ARCHITECTS JOURNAL. 



LSeptbmbee, 



The total receipts enumerated in 181-7 were about £l9,000, and 

 those for limestone and lime iii 11,000; making about ii30,000 

 enumerated. 



Tlie rates for the conveyance of building and paving stones are 

 as follows : — 



Per mile per ton. 

 Arbroath and Forfar, 2 50i/. 



Marj port and Carlisle, 2 04 



Laucasbire ami Vorkliire, l'%3 



Lunduu and South Western, 2 50 



I'reston and Lon>;ridge, 3 00 



St. Helen's and Kiincorn, 112 



Wisliaw and t^oltness, 2 50 



York and North Midland, 100 



The greatest traffic in building, paving, and limestones, and in 

 lime, is carried on by the following companies : — 



Tons. £ 



York and North Midland, 10),0ii0 10,300 

 Midland 



Newcastle and C'aili«Ie, 

 IStucktun and Darlington, 

 Preston and Lon^ridge, 

 Stockton and Haiilepool, 

 Wisliaw and CoUuess, 



PLAN-PRICKING INSTRUMENT. 



Sir — Amongst other duties, I am engaged in making a most 

 extensive and minute survey of a large city, showing every house 

 and all the drainage throughout, the scale being very large — 

 1 inch to 100 feet ; and I am preparing duplicate fair copies of 

 each sheet, which is being done by pricking through all the sheets 

 at once, the original working drawing being placed uppermost. 

 In doing this with the common prickei, I fouud that the draughts- 

 man did not hold the pricker perpendicular ; consequently, the 

 lower sheets could not be accurate copies of the original. To 

 obviate this, I have contrived an instrument, by which any atten- 

 tion on the part of the draughtsman in keeping it perpendicular 

 is not required: all he has to do is to be careful that he pricks 

 through the proper points of the plan correctly; the holes are 

 then sure to be vertically under one another, let the sheets of 

 paper be ever so numerous. 



Elevation. 



Plan. 



The engraving is apian and elevation of the instrument, the full 

 size. The arch a, is of brass, with a cylindrical crown A, in which 

 a piston e, works. At the lower end of the piston the needle- 

 point is fixed; the arch is moved over the paper until the needle- 

 point is precisely over the spot to be pricked through ; the finger 

 then presses on d, the top of the piston, which effects the punc- 



ture; and upon relieving it of the pressure, the spiral spring 

 wound round the piston immediately raises it, and withdraws the 

 needle-point from the paper; — in this way the work is done both 

 correctly and rapidly. 



To prevent the needle passinJ^• far through the paper and making 

 a large hole, or sticking into the drawing-board, 1 have had a sheet 

 of zinc to cover the board, and fastened down to it. This zinc 

 sheet being a little less in size than the drawing-paper, admits of 

 the latter being all (one upon the other) pinned down to the board 

 round their edges, which overlap the edges of the zinc. I find the 

 zinc to be very advantageous in use, as it causes the needle to 

 make no other than extremely fine holes. 



STREET PAVING. 



Sir — It is not necessary at this time to revive the controversy 

 formerly raised between the respective advocates of wood and stone 

 paving ; experience or experiment — that great test of truth — will, 

 ere this, have determined the opinions of most persons, as to the 

 relative value or conditions of applicability of the two systems. 

 It may not, however, have been considered how far combinations 

 of the two might be made with advantage — adapted especially to 

 certain cases. 



The repairing of Holborn-hiU, consequent on the recent removal 

 of the houses on the north side of Holborn-bridge, brings to consi- 

 deration the inconveniences — nay, dangers, occurring to the carriage 

 traffic on declivities such as this, with any mode of paving hitherto 

 adopted. 



The placing of the granite stones obliquely to the line of surface, 

 whereby the edges of the stones formed a series of sharp angles or 

 steps (thus giving a rough surface and good foot-hold for horses 

 drawing up, and obstructions to the too rapid sliding of wheels 

 down the hill), appeared a vast improvement — and truly would be 

 so, if the uneven surface thus obtained were not rapidly worn oif by 

 the continued traffic, and especially by the action of the drags on 

 the wheels of carriages descending the hill. Thus the surface soon 

 becomes smooth and slippery, whatever be the material used or 

 form of laying, whenever the material is of one and the same kind, 

 and consequently of equal wear throughout. 



If, however, we employed materials, in conjunction, of different 

 characters and rates of wear, we should then maintain inequalities 

 of surface, affording continuous foot-hold for horses, and obviating 

 existing defects. 



Suppose that between each course of granite paving there were 

 placed a thin course of wood, then the difference in the wear of the 

 two would give the effect desired. 



ji 



The annexed sketch shows the arrangement. A course of granite 

 stones. A, to be laid in the usual way across the road, being about 

 three inches in thickness ; following this with a plank of wood, 11, 

 one inch thick, and of the depth of the granites ; then following 

 on with stones and planks in alternate courses. 



Let us not stand arguing doubts and probabilities, but put the 

 question to the true test — experiment. This can be done within a 

 small space, and at little cost. 



J. L. 



ffampstead, Augxist 8, 1848. 



[A plan Bometliing aimilar to tbe above has been tried tn Ctieapsi'le and in Piccadilly, 

 bm iieiiher was ot vvooJ. They both produced a veiy disugrcciLic rullliiig and jolliuu m 

 the carriage .J 



