Page:The Building News and Engineering Journal, Volume 22, 1872.djvu/474

 452 arrange such work for them as would enable them to earn, not the full wages of ordinary labourers, still less such wages as they had been accustomed to, but something that would provide them with sufficient to live upon without actual want of necessaries, and to allow those who were comparatively able to earn as much as they could. The following was one of such cases :— The men (about 80) had been at work for 6 weeks stripping soil and removing earth— baring a thick bed of clay—at the price of 1d. per square yard for soil stripping, and 4d. per cubic yard for baring the clay. The average running of the top soil was 75 yards, that‘of the baring 60 yards. The men earned at these prices Is., 1s. 3d., and 1s. 6d. per day, varying with the strength of the men in the various gangs; each gang consisting of 6 men, to whom a width of face of 9 yards was alloted. These earnings being unsatisfactory, it was required to determine whether the prices were sufficient and such as ordinary labourers can earn fair wages at, for which purpose the following calculations were made :— Taking the mean distance, there are in each gang of 6 men 1 getter 2 fillers 1 spurner out 2 runners 6 The quantity of earth excavated and removed varies as the number of fillers. Here are 2 fillers. An ordinary labourer usually fills 15 cubic yards of this kind of earth in a day of 10 hours. Then 2 fillers fill 30 cubic yards a day, which is got by 1 man and removed by 3. Taking the wage to be earned by each man at 3s., the daily wages of the gang would be 18s., for which 30 cubic yards would be excavated and wheeled 60 yards ; that is, at the rate of 7d. per cubie yard. The factory operatives are not able to do so much work as navvies are, therefore they will earn at this price less than 3s. per day. To ascertain how much per day they would earn at this price, take the quantity of work done by them. The quantity they have re- moyed per week, on the average, has been as follows :— Cubic yards. Oubie yards. No. 1 gang 93 in 4§ days ee 194 per day. NDS tk 108 ind days = 214 o No. 3 97 ind days = 193 Ps No. 4 ,, $4 ind days = 19 A No. 5 ,, 147 in6 days = 244 is NOSE 4. 101. in 44 days ca 204 1 NO. 7) s,; 121 %in6é days = 20 ui No. 8 ,, 9 in 5 days = 17 ) No. 9 ,, 110 in 44 days = 244 No.10 ,, 25 in6é days = 21 a Total 1,090 in 52 days = 21 average. Taking 2 fillers in each gang, each man fills 10} cubic yards a day, but say 10 cubic yards, then the wage he would earn, at the Same price at which a navvy would earn 3s., avould be 15: LD = 12) O80 28. It was considered that if work were found for the ‘‘operatives” on this basis it would greatly relieve the funds subscribed so handsomely for their relief all over the country, but the practical effect was not great, in general, although in a fey places the authorities were able to organise something like a system which worked pretty well, but the very great changein every way disquali- fied these men for such work as this men- tioned. But they were very willing to work, if it could be properly arranged for them. The great difficulty was in placing them along with navvies, for although there was not that ill-feeling to them that English nayvies some- times (very ignorantly and very stupidly) display when Irishmen are put to work along with them, yet the disproportionate strength of the two made it very doubtful whether an addition of 20 operative to 100 navvies was any advantage to the work, notwithstanding that’ they were kept as much apart as possible. THE BUILDING NEWS. Fencing more appropriately belongs to earthwork than to any other part of a public work. The following prices have been paid : Preparing the border, or cop, for quicks, 4d. per rod of seven yards. Number of sets per yard 12, or 84 per rod. The quicks are three years old, transplanted, and cost 10s. per 1000; 84, therefore, cost about 10d, making together 1s. 2d. per rod. Larch post and rail fencing, posts 6ft. long, Gin. by 3Sin., set 2ft. into the ground, 9ft. apart ; 4 rails, each 10ft. long, 54in. by 14in., scarfed inthe posts; prick post 4in. by vin. driven in the middle of each length, to which the rails are nailed, 1s. 6d. per lineal yard. The sandrock hereinbefore mentioned was got up by crowbars, wedges, and hammers, for the most part, requiring blasting only occasionally ; but harder and more compact rock requires the constant use of powder or other explosive agent, as gun-cotton, nitro- glycerine, or litho-fracteur; but we intend to speak only of powder, having had no ex- perience with any other. Blasting powder is coarse-grained and weaker, pound for pound, than gunpowder, in the proportion of about 2to3. It does not ignite so suddenly, and is for that reason supposed to be preferable to the stronger powder for blasting purposes, besides being cheaper, the supposed superiority lying in the fact that its action is that of heay- ing rather than that of a sudden blow ; but the preference would seem to be more a matter of fancy and caprice than of proof and reason, for it is reasonable to suppose that as rocks are brittle, a sudden blow would have a better effect in shattering the mass. Another reason for the preference may he, in some cases, that it is difficult to prevent workmen using too much powder. Some of them try in that way to effect an amount of work that would be more easily attained by a closer examination of the rock, to ascertain the lines of least resistance, and so to plant the drill or jumper as to loosen the largest quantity of rock with the least expense of powder. Too much powder pro- duces chiefly noise, and a noisy shot seldom does much work. But where rocks are blasted for mercantile purposes, such as to be cut up into blocks, the same reason may not hold good as where the object is merely to excavate the material and remove it, the useful produce, if any, being used as rubble stone. Holes are made either with a drill or a jumper, the former being struck with a hammer, and the latter effecting its progress by its own weight after having been lifted up to some height and released, this being usually done by two men, and the other by one or two men striking while a boy steadies the drill. In either case the tool requires to be turned gradually round during the operation. <A drill is but little longer than the depth of the intended hole, for if it is of great length, the jarring of the blow destroys part of its effect, but a jumper is 7ft. or 8ft. long, and as its effect proceeds from its centre of gravity, the jarring is that due to only half its length. It has a head at eachend. Drills are used for short holes, and jumpers for deeper ones. The ends of both sorts are made of steel. We are speaking only of ordinary work. Great blasts are effected in a different manner, but neither they nor quarry work on a large scale concern our subject, which goes only to the excavation and removal of earth and rocks, the removal being the main purpose. Jumpers, such as we have mentioned, are generally 1+in. or 14in. diameter, and can only be used for holes that are vertical or nearly so, And here we are reminded how different names come to be givento tools in different parts of the country, or in different kinds of work. Thus, both the drill and the jumper (as we deseribe them) are called jumpers in some places, the distinction on the work being made by calling one the jumper and the other the churn-jumper, from the resemblance of the manner of using it to the act of June 7, 1872. churning, but in our experience the term jumper has always been applied to a tool which is lifted up by force and suddenly released, cutting its way by its own weight ; and the term drill, for the sake of distinction —which is practically necessary—has been applied to that tool which is driven by blows uponit in all open cuttings ; in driving head- ings, however, where the jumper proper is never used, the drill is called indifferently by either name. The hole having been drilled or jumped, water being poured down occasionally to assist the operation, and the loose stuff re- moved from time to time with the scraper, the bottom is dried with wisps of hay or tow, and the charge of powder poured in through afunnel. The old method was—and is yet sometimes—then to insert a “needle,” a small copper rod, of a length a little greater than the depth of the hole, into the powder ; the hole left by which when it was withdrawn is filled with fine powder, or straws filled with fine powder are put down it into the charge, the priming thus formed being fired with touch-paper ; but as it is a very dangerous method, the more usual way now is to use the safety fuse, consisting of a core of powder surrounded by a hemp cord, var- nished, to protect the core, and covered with whitening to prevent the varnish from adhering. When the needle is used there is great risk of igniting the charge in the operation of filling up the space round the needle with the tamping iron. ‘The use of the safety fuse is in every respect preferable. The fuse is cut to a length a little greater than the the depth of the hole, and one end inserted into the charge of powder, the other end being bent over the side of the hole. Upon the powder a wad of hay or turf is placed, and then a handful of loose stuff is thrown in and rammed down with a tamping iron, and so on successively to the top. The best stuff to fill the hole with is coarsely-powdered burnt clay, next to that dry clay, or loose sand where the holeis deep. The direction in which the explosion takes place is in that which offers the least resistance, and evidently true as this is, it seemsto be often overlooked by workmen. No amount of tamping with any kind of stuff will make the resistance of the filling equal to the same length of solid rock, and the least effect is produced (and consequently the greatest waste of powder) when the line of least resistance is in the same directionas the hole. When the rock is fissured the holes should be made in such positions as will give a line of less resistance in the direction of the fissure or of the face than in that in which the hole is drilled, for a mass detached only slightly from the surrounding rock can be cut up with wedges and hammers at less cost than would be necessary to blow it to pieces with powder. In rock that lies in layers, whether horizontal, inclined, or verti- eal, the shots should be put in in the line of the layers, and not at right angles to them ; the effect of a given charge of powder being much greater in splitting the rock in this manner than in bursting up the layers of rock, and when this cannot be exactly done it should be approximated to as nearly as possible. The quantity of powder should in all cases be proportioned to the length of the line of least resistance, and not to the depth of the hole, as is frequently done. The abso- lute quantity of powder required to loosen a given quantity of rock varies so much with the kind of rock that no fixed quantity can bestated, but when once ascertained for any particular kind, for any given length of line of least resistance, the proper quantity for any other hole may be estimated on the basis that it is proportional to the cube of the line of least resistance. Thus, if a hole be bored in which the line of least resistance is 2ft., and 4oz. of powder are found to be suflicient to loosen a certain mass, then if another hole be bored in the same kind of rock where the line of least resistance is 4ft., the quantity of