EFFECTS OF SPECIFIC MANURES. 191 



Art. XLII.— experiments ON THE CONTINUED 

 EFFECTS OF SPECIFIC MANURES. 



Drawn tjp by Mr. A. Murray, Nethermill of Cruden. 



From the results of three years' experiments of the rota- 

 tion, Mr. Murray says the following- conclusions may be 

 drawn : — 



1st, Farm-yard manure with guano, seem to g-ive the 

 greatest bulk of crop, and a heavier crop than a fidl manur- 

 ing' of either alone. 



2d, Farm-yard manure with bone-dust, or bone-dust and 

 sulphuric acid, produce heavier crops of turnips and oats 

 than a full manuring' of either alone. 



3d, Notwithstanding- the weight of hay crop, after the 

 bone-dust, or bone-dust and svdphuric acid, appears about 

 equal to that raised by the other applications, still they 

 uniformly produce the best sole of rye-grass and white 

 clover. This may be accounted for in two ways. 1st, 

 Much more phosphates are added to the soil by a full 

 manuring- of bone-dust, or bone-dust and sulphuric acid, 

 than from farm-yard manure or guano. The same result 

 holds good with mixtures of these. 2d, The texture of the 

 soil is much firmer in the txu'nip crop after bone-dust, or 

 bone-dust and sulphuric acid, than after farm-yard manure 

 or guano. Now, experiment and experience have proved, 

 of late years, that the texture of the soil has much influence 

 in the growth of clover. 



4th, The addition of sulphuric acid to bone-dust, appears 

 to accelerate the growth of vegetables. This is an im- 

 portant circumstance for wet cold clay soils. I find, that a 

 less quantity of sulphuric acid along- with bone-dust, than 

 that used by the Turrift' experiments — say, 6 lb. instead of 

 25 lb. to tlie bushel, has all the advantages of early action, 

 and is free from the objections to so large a proportion. 



5th, With regard to farm-yard manure, or peat and saline 



manures, they fall behind the other applications after the 



first year. This may arise from the saline manures being* 



• easily dissolved, and thereby early ^appropriated by the 



plants. 



