390 Br. F. H. Hatch — Iron-ores of the United Kingdom. 



regulations work could neither be compelled by force nor by 

 a redaction of rations. The difficulty was overcome by the intro- 

 duction of piece-rates ; but only to a limited extent, as there was no 

 outlet for surplus earnings in the canteens, food supplies having been 

 cut down on account of the general food shortage. 



The dearth of quarryrnen led to active steps being taken in 

 responsible quarters to supplement and to increase the efficiency of 

 manual labour at the quarries by the provision of mechanical 

 appliances for stripping, breaking, and loading the ironstone. 



In these open-workings, the output per man employed varies with 

 the thickness of the ironstone bed, the amount of cover to be removed, 

 the use made of mechanical appliances, and the condition of the 

 weather. The weather materially affects the output, especially 

 where hand-labour is concerned. From returns made to the Ministry 

 of Munitions in December, 1917, it appears that the average output 

 in the Midlands per man employed was five tons per shift, and that 

 it ranged from 3 - 8 tons where hand-labour was alone employed, to 

 over fifteen tons where mechanical excavators were in use under 

 favourable conditions. The actual saving of manual labour which 

 resulted from the installation of mechanical plant in the ironstone 

 quarries during the War is estimated to have been equivalent to over 

 3,000 men. 



The Jurassic ironstones have a wide distribution both in this 

 country and on the continent. In 1913 Germany mined, in 

 Lorraine and Luxemburg, 28,000,000 tons of Minette ores of 

 Jurassic age, out of a total production of 36,000,000 tons of iron- 

 ore, while she imported in addition 3,800,000 tons of the same 

 ore from Briey. Without the Lorraine iron-ore basin, which she 

 stole from France in 1871, Germany would have been unable to go 

 to war, and she took care to secure the remaining portion of the 

 field (i.e. the Longwy and Briey basins) soon after the commence- 

 ment of hostilities. One of the best guarantees for future Peace 

 is the provision in the Peace treaty that no portion of this iron- 

 ore field remains in German hands. 



In England the Jurassic formation stretches as a broad band 

 from the coast of Yorkshire to that of Dorset. The ironstones 

 occur on four different horizons : — 



The Jurassic Ironstones. 



Name of Ironstone Position in Jurassic TT77 , -, 



•4, -j o i Where worked. 



Bed. System. 



Westbury and Dover. Corallian. Not now worked for iron. 



Northampton Ironstone. Lower part of the Inferior Kutlandshire and North- 

 Oolite, ampton. 

 Marlstone. Upper part of the Middle Cleveland in Yorkshire, 

 Lias. South Lincolnshire, 

 Leicestershire, and 

 Oxfordshire. 

 Frodingham Ironstone. Middle part of the Lower North Lincolnshire. 

 Lias. 



The Corallian ironstones are at present not worked as a source 

 of iron, although the Westbury bed is quarried for use in the 



