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 INDUSTRIES in length and breadth, and are squared both sides and at one end, but are much larger, only about 130 being required to a square. These until recently were used for cattle sheds and farm buildings. The slater in using the scantle and rags has to shape them according to require- ments. The rags make a stronger roof than sizes, being thicker and generally rather coarser. The roof does not present so even a surface as when made of sizes, and this is a feature which some architects have of late years been favouring. During the last five years they have been used in various parts of the country on large build- ings not of the class named. Slate is used for many purposes besides roofing, such as floors for kitchens, halls, and lighthouses, for dowels to connect granite blocks in lighthouses, for win- dow sills, corn chests, brewers' vats, ridge rolls, urinals, chimney-pieces, and for water cisterns up to 2,000 gallons. These goods are prepared in sheds which are distinct from those for the manufacture of roofing slate, and furnished with the necessary sawing machines, planes, and other appliances. The veins or beds of slate-rock run in various thicknesses, from 2 ft. to 10 ft. with a dip from east to west of about 3 in. in a foot, with a slight inclination from north to south. In some beds a small quantity of quartz is found mixed with the slate, and sometimes this prevails to such an extent as to render the slate useless for commercial purposes. The colour of the slate is grey blue, and the quality continues to be good and quite maintains its former prestige. Twelve and a half cubic feet weigh one ton. The number of persons employed from time to time has varied. In 1850 it was about 600. Five years later a reduction took place by the discharge of the women and girls who up to that time had been employed as slate-splitters. In justice to the women it may be said that as regards ability they were equal to the men. Up to 1871 the number of employes had nearly reached 600, but in that and the two following years the number was reduced to 466, and with slight variations so it has continued, the number at the present time being 463. The output of rubble and rock has varied con- siderably from time to time. The earliest date for which it can be given is 1873, when the total quantity was 242,146 tons. In 1880 it was 359,549 tons, which is the largest on record. In 1893 it was 147,093 tons, and in 1903 it was 274,105 tons. The value of the products for the past three years may be reckoned as ap- proaching 34,000 a year. The price has varied considerably during the last 50 years, and has quite if not more than doubled. There are now eight stationary steam engines, two of which are used for hauling rubble and rock over the inclines. Arrangements are in progress for adding another engine to the main incline, which is about 1,000 ft. long, and has 521 an inclination of 5 in 12. One engine will continue to be used for hauling to the parapet- head, one for pumping water, and three for driving the machinery in the manufacturing sheds and in the engineering, carpenters', and smiths' shops. Two locomotives take the wagons to the manufacturing sheds and rubble tips. Cranes and derricks are used in various parts of the works. The general method adopted in the produc- tion of roofing slate, in the working department, is as follows : The men who blast or raise the slate-rock in the quarry and the splitters and dressers in the sheds are partners and usually share equally, so that the more care and good judgement, exercised in preparing the blocks the better for each man, and also for the shareholders. Many comparatively rough blocks are refused by the contract men, and these are passed on to men and boys called cullers, who are paid a fixed price, and make as much out of them as they can. The sawing and planing are paid for by the foot. Filling the wagons in the quarry, landing at the parapet-heads and incline, and tip- ping at the deposit end are performed at so much per ton. Everything taken from the quarry passes over a weighbridge. A quarry- man's wages average about 2is. per week. Fillers and others earn about I Ji, It should be observed that it is only during the last fifteen years that circular saws have been gradually introduced for cutting the large pieces of slate, which is done at right angles to the cleav- age, after they have been divided into thicknesses of two or three inches. When the saws are not used the slate is cut by a process called flerrying. In this the stone is laid flat, and with a gouge a small groove is chipped in one side ; a chisel is then placed in the centre of the groove and is struck with the hammer until the effect of the blows is seen in a small crack dividing it into two pieces. The disadvantage of this method is that the split frequently goes in the wrong direction and waste follows. This plan is still pursued to some extent at Delabole, and alto- gether in the other two quarries. Until the introduction of saws it was the only method employed in this and all other quarries in Corn- wall. So far no machinery has been introduced for the splitting of slate, but slate-dressing ma- chines have been used for some years at Delabole, and are now in general use. Previous to the construction of the London and South Western railway line to Wadebridge, the slate, sent by water, was shipped at Port Gavorne, about five miles distant from the quarry. The wagons were brought alongside the vessels, and the slate was passed from the wagons to the vessel by women and men. Sixty years ago the wagons were drawn by two bullocks and a horse, afterwards by horses owned principally by small farmers, who did this in connexion with their farm work. The London and South Western 66