GEOLOGICAL DISCOVERIES 155 



Hitcham, of which he became the Rector in 1838, from those 

 at Cambridge, he by no means neglected science ; but he 

 utilized it in different ways. Thus having a good knowledge 

 of chemistry, he endeavoured to make the farmers interested 

 in more scientific methods of farming than they had been 

 accustomed to. He gave lectures on the fermentation of 

 manures and he wrote fifteen " Letters to Farmers," first 

 published in the Bury Post and then separately. He even 

 proposed that they should make experiments themselves. For 

 this purpose he issued schedules to about 70 farmers who 

 asked for them. 



The experiment was to test Liebig's suggestion that gypsum 

 should be added to manure heaps to fix the ammonia. Un- 

 fortunately there is no record of the results^ 



The most important discovery from an industrial point of 

 view, due to his knowledge of Geology, was undoubtedly that 

 of the phosphate nodules known in the trade as "Coprolite," at 

 Felixstowe in 1843, when he and his family were staying there. 

 The cHffs are formed of "London clay," topped by the "Red 

 Crag," between which is a bed of rolled, brown pebbles, once, 

 with the crag, forming an ancient beach. Where the white 

 " Coralline^ " Crag occurs, the pebble bed lies below it. This 

 accounts for the fact that it contains remains of Miocene 

 animals, such as teeth of the Hipparion, or ancestor of the 

 horse. 



As the sea is always encroaching, the cliff has much " talus " 

 in places, upon which was strewed the debris from the crag, 

 including vast quantities of pebbles. Observing that they often 

 contained a shark's tooth or other organic remains, he suspected 

 that they might be composed partly of phosphate of lime. 

 This proved to be the case, for the first analysis made by 

 Mr Potter of Lambeth showed 54 "/o (1844). He communi- 

 cated the fact to Mr, subsequently Sir, John Bennet Lavves, who 

 desired a ton of nodules to be forwarded to him for experiment. 



^ On enquiring at Rothamstead, Mr Hall has kindly informed me that a "good 

 deal of attention was given in Germany to this and other possible materials for the 

 conservation of the nitrogen; but the general result vv'as adverse to their employment." 



^ A misnomer, as the coralloid organisms are Bryozoa. 



