17 



water is poured in, and by continued attrition the mud and clay 

 are separated from the nodules, the latter being left clean at the 

 bottom. The refuse water, which the workmen call " slurry," is 

 conducted away by channels cut in the slope of the mound upon 

 which the mill is erected, to pass off into a drain or pool on the 

 surface of the land prepared to receive it. There it lies for a 

 year to dry up, when the mud at the bottom is ready for carting 

 away, and mixing as manure with the soil after spreading. 



The nodules thoroughly cleansed in this way form a heavy 

 mass, three pecks and a quai;ter going to the hundred weight, 

 and a bushel making about ten stone. Among them are many 

 shells and other fossils in an entire state, though the large 

 proportion consist only of fragments of animal remains, Avorked 

 up with clay and other earthy pai'ticles. 



After drying and weighing, they are taken to the Railway 

 Station and sent up to London. Whole strings of trucks full of 

 them may often be seen at Cambridge, the trucks being kept for 

 this traffic and labelled accordingly, the number of them 

 indicating the largeness of the business for which they are set 



apart. 



Arrived in London, the nodules undergo the process of 

 grinding, after which they are dissolved in sulphuric acid, and 

 then mixed up with other ingredients to form an artificial 

 manure, or " super-phosphate," coming back again to the farmers 

 in bags, and sold at prices varying from £8 to £12 per ton. 



The manure thus obtained, I am told, is used for drilling in 

 with turnips and other root crops, and also usually for barley. 

 Care, however, must be taken that sufficient burnt earth and 

 ashes are- mixed with it, lest it should "burn" and destroy the 

 seed instead of encouraging it to grow. 



The details above given relate exclusively to the Green-sand 

 nodules found in Cambridgeshire. With the Suffolk diggings, 

 which, though considerable, I believe are not quite so extensive, 

 —I am less acquainted, Mr. Rodwell, however, a Member of 



B 



