ALLEGED IMPOVERISHMENT BY CALXING. 235 



when in the state of carbonates.* That such extension is correct 

 is further confirmed by some of the effects of calcareous manures, 

 as adduced by Prof. Johnston, and as understood by practical 

 limers in England. He says, of the action of lime, " it changes 

 the inert vegetable matter in the soil, so as gradually to render it 

 useful to vegetation (p. 400) ; and further (p. 401), that " under 

 the influence of lime, the organic matter disappears more rapidly 

 than it would otherwise do ; and that, after it has thus disappeared, 

 fresh additions of lime produce no further good effect." These 

 results, in substance, have been maintained in the preceding por- 

 tion of this essay ; but were ascribed there to other than the gene- 

 ral solvent action of calcareous earth which I would now suppose 

 to be one of the important concurring causes. 



According to the treatment of the land while this solvent action 

 of calx is proceeding, through a course of years, the general and 

 final results will be either injurious, in the removal and destruction 

 of the organic matter (as stated by Johnston), or beneficial, by its 

 being stored up and fixed in the soil, under reverse circumstances. 

 If .the system of cropping be continually exhausting taking as much 

 as possible from the land and returning nothing then the lessen- 

 ing and disappearance of the organic matter, whether slowly or 

 speedily, will finally be complete ; and equally sure will be the so 

 induced and almost hopeless subsequent sterility of the soil. It was 

 upon such ignorant and destructive cropping as this that was 

 founded the often quoted old proverb in England, that u liming 

 makes rich fathers and poor sons." And this saying will be cer- 

 tainly true, if understood of liming (or of calxing in general), 

 followed by continued or generally exhausting tillage ; though en- 

 tirely false if followed by mild meliorating cultivation, and judi- 

 cious management. Doubtless there were formerly in England, in 

 times of ignorance and bad farming, numerous cases of the destruc- 

 tive results of calcareous manures j and it is much to be feared, 

 that, from as ignorant practice, and at some time hence, there will 

 be many such results in this country. Some such have already 



* Both passages have before been quoted, in reference to other subjects. 

 Rennie says of insoluble humic acid, that it "readily combines with many 

 of the substances found in soils and manures, and not only renders them, 

 but itself also, easy to be dissolved in water, which in their separate state could 

 not take place. In this way humic acid will combine with lime, potass, 

 ammonia, in the form of humates, and the smallest portion of these [alka- 

 line matters] will render it [the humic acid] soluble in water, and fit to be 

 taken up by the spongelets of the root fibres." (Alphabet of Scientific Gar- 

 dening. ) 



Thaer says " It is well known that with the aid of alkalies, ashes, 

 lime, and marl, humus may be deprived of its acidity, and rendered easily 

 soluble." (p. 538.) 



