REPORT OF THE CHEMIST 



187 



SESSIONAL PAPER No. 16 



MARL. 



During the year several samples of this naturally-occurring amendment have been 

 analysed 



Analysis of Marls. 



No. 1. — A deposit from Mabou Harbour Mouth, N.S., containing about one-third of 

 its weight of carbonate of lime. Though of somewhat poor quality, it is 

 likely to prove of value for soils needing lime. 



Nos. 2 and 3 are shell marls of excellent quality, from the neighbourhood of New 

 Richmond, Quebec. 



No. 4. — A very good shell marl from S. R., Grey county, Ontario. 



Marl is an amendment of considerable value for all soils that would be chemic- 

 ally or physically benefited by lime. It may be used to improve the texture or tilth 

 of both heavy clays and sandy loams, to neutralize sourness and promote nitrifica- 

 tion, and as a supplier of lime (an element necessary for plant growth) for all soils 

 deficient in that constituent. From these functions, marl, it will be seen, may be 

 used to advantage on a very large class of soils, but it cannot be regarded as a substi- 

 tute for barnyard manure. Neither can it rightly be styled a fertilizer, a term 

 restricted in commerce to those materials which furnish one or more of the essential 

 constituents of plant food — nitrogen, phosphoric acid and potash. 



Marl is known sometimes, agriculturally, as ' mild lime,' and this term is justified 

 largely by the fact that an excessive application does not work that injury to the soil 

 which follows large applications of quick or caustic lime. 



GYPSUM OR LAND PLASTER. 



Gypsum is a naturally-occurring sulphate of lime, and samples of good quality 

 show very little foreign matter. When crushed or ground it forms the well-known 

 land plaster. Three samples are now reported upon. 



