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remains, may be valuable as an element in the doil, or as a me- 

 chanical divider of the soil, but no farther. It is not an en- 

 richer of the soil. Though in the form of a carbonate, it gives 

 out its carbon with an extreme reluctance. As constituting 

 an element in the plant itself, the amount required for any plant 

 is so small as to deserve very little consideration, and, from its 

 being found every where in sufficient quantities to form the 

 eggs of birds, and the bones of animals, it may be regarded as 

 every where diffused in equal sufficiency for the purposes of 

 vegetation. In its application to peat composts, it assists in 

 their decomposition, but here likewise its tendency is to expel 

 the ammonia, to drive off the enriching parts of the manure, and 

 to reduce much of the remainder to an insoluble state. Here, 

 however, its pernicious effects may be counteracted, where 

 there is a sufficient covering of mould to absorb the gases, 

 which would otherwise be dissipated in the air. Under such 

 circumstances its use may sometimes be advised. 



The ill-success of Mr. Haggerston, in his application of bone 

 manure, does not, as he sensibly remarks, imply that it may 

 not be very efficacious in other situations. If the bones, from 

 which his manure was obtained, had passed through the soap- 

 boiler's hands, or had been long bleaching in the rain and air 

 and sun, there remained only the phosphate of lime, an import- 

 ant element in vegetation, but of which perhaps there was al- 

 ready a sufficiency in the soil. Had these bones been full of 

 animal matter, it cannot be doubted that their efficiency would 

 have been seen. Of the poudrette, too, in the use of which he 

 seems to have been equally unsuccessful ; before deciding against 

 its efficacy, it would be desirable to know the composition. 

 No one questions the extraordinary power of human excre- 

 ments ; but what other substances were in this case combined 

 Avith them, and in what proportions, does not appear. They 

 may have been such, or furnished in such proportions compared 

 with the material which they were designed to neutralize, 

 as to render the actual amount of night-soil applied insuffi- 

 cient to warrant the expectation of any marked effect. If it 



