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most deposit of all, is about six or eight feet of diluvial sand and 

 gravel. In the descending order the beds are: 



1. A light-coloured bright greensand, very free from any- 

 foreign substance, if we except a moderate share of greenish 

 clay. It has all the aspect of the light-green or upper marl of 

 many other localities, the efficacy of which has been proved in 

 some cases to be equal to that of the darker stratum which lies 

 beneath ; notwithstanding which, the farmers of the vicinity deem 

 it to be quite inert, and therefore erroneously call it a clay. It is 

 admitted that very imperfect attempts have been made in using 

 this material as a manure, and I cannot but believe that a too 

 precipitate judgment has been passed upon it ; for, as the follow- 

 ing exhibition of its chemical constitution shows, it differs but 

 little from many marls of long acknowledged efficacy. Its com- 

 position, it will be seen, does display a less than ordinary propor- 

 tion of potash. 



. Analysis of the light-green Greensand of Mullica Hill. 

 Composition. — In 100 parts : 



Silica, ... - 52-32 



Protoxide of iron, - - 27*56 



Alumina, - - - 8-94 



Potash, ... - 5-50 



Water, ... - 5-42 



99-74 



2. A chocolate-coloured bed, in which about one half is the 

 green granular matter and one half a fine clay of a light purple 

 or chocolate tint. This also has all the features of a good marl, 

 though it is not reputed to have any power. 



3. A thin seam, not more than a foot in thickness, of a dark 

 bluish-green marl, unquestionably very good. 



4. A bed consisting of dark greensand and shells in the state of 

 casts ; the shelly matter being all replaced by oxide of iron. 



5. A dark yellow ferruginous sand, with casts of shells and 

 ferruginous concretions, and a small proportion of the green 

 granules. 



6. A dark yellow ferruginous sand, almost entirely free from 

 the grains of marl, and containing no trace of organic remains. 



24* 



