'204< ON THE COMPOSITION OF SOILS, &C. 



" facts which seem very strongly to militate 

 *' against it, and, indeed, he himself seems to 

 " proceed upon a theory altogether different. 



" Calcareous matters alone (says he) is not 

 <* capable of rearing plants to perfection : 

 " mould is necessary to mix with it in certain 

 " proportions, before it can form a proper soil. 

 *' It remains, however, to be determined what is 

 " the due proportion of these ingredients for 

 *' forming a proper soil. 



" We know that neither chalk, nor marl, nor 

 ** lime, can be made to nourish plants alone ; 

 " and soils are sometimes found that abound with 

 " the two first of these to a faulty degree, but 

 " the proportion of calcareous matter in these 

 " is so much larger than could ever be produced 

 " by art, where the soil is naturally destitute of 

 *' these substances, that there seems to be no 

 ** danger of erring on that side. Probably it 

 " would be much easier to correct the defects of 

 " those soils in which calcareous matters super- 

 " abound, by driving earth upon them as manure, 

 " than is generally imagined; as a very small 

 ** proportion of it sometimes affords a very per- 

 " feet soil. I shall illustrate my meaning by a 

 " few examples. 



*' Near Sandside, in the county of Caithness, 

 " there is a pretty extensive plain on the sea- 



