. Discovery. Science. 1S4 DISCOVERY tinguished from the " Middle Chalk " in North Lin- colnshire, by means of certain fossils which it contains but which do not occur in the lower two divisions. It consists of a hard white chalk, So feet or so in thickness, with numerous thin layers of flint. Fig. I shows a general view of part of one of the two mx-^. ^'iX'i â -â f'' ^'^' Fig. 2.âview showing METHOD OF WORKING AND EFFECT OF WEATHERING ON CHAI^K. great quarries at Melton Ross situate on the main line between Sheffield and Grimsby, which passes between them on a high natural emban
. Discovery. Science. 1S4 DISCOVERY tinguished from the " Middle Chalk " in North Lin- colnshire, by means of certain fossils which it contains but which do not occur in the lower two divisions. It consists of a hard white chalk, So feet or so in thickness, with numerous thin layers of flint. Fig. I shows a general view of part of one of the two mx-^. ^'iX'i â -â f'' ^'^' Fig. 2.âview showing METHOD OF WORKING AND EFFECT OF WEATHERING ON CHAI^K. great quarries at Melton Ross situate on the main line between Sheffield and Grimsby, which passes between them on a high natural embankment of chalk that has not been quarried. These quarries, each 175 yards long by 100 yards wide and 50 feet deep, have been worked for many years for whiting, and lime for building and agricultural purposes, but the bulk of the output is used for fluxing steel in furnaces. The chalk, or " Limestone " as it is called locally, is won simply by pick and shovel, and occasionally by blasting. It is quarried out in steps or ledges as shown in Figs. I and 2. For making whiting, which is chemic- ally pure chalk, there are pan-mills to grind to a paste the pure white beds of chalk which occur in certain parts of the quarry. The slurry or liquor from the pan-mills is run off into settling-pits, from which the paste is dug out by hand and placed in lumps on shelves in long open sheds where it is dried by the air. A certain waste-product is removed from the slurry before it enters the settling-pits. This product is coarse in grain and cannot be used in the manufacture of whiting, although its chemical composition is identical with that of whiting. The process is quite simple ; but good raw material such as is to be foimd in the " Middle Chalk " is in- dispensable. The manufacture of lime, and of the purer variety of lime for steel-smelting, is also carried out in brick kilns in one of the quarries. The process consists of burning the chalk (calcium carbonate) into l
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