Experhnents upon Swedes. l77 



On analysis it yielded in 100 parts : 



Moisture 6"86 



* Organic matter 13'14: 



Phosphates of lime and magnesia (hone-earth) .. 68'17 



Carbonate of lime 6.79 



Alkaline salts 1-90 



Insoluble silicious matter (sand) 3-42 



100-00 



* Containing nitrogen 1*83 



Equal to ammonia 2*22 



Although sold as the finest bone-dust, this article was, in 

 reality, a mixture of about equal parts of fine bone-dust and com- 

 mercial powdered bone-ash. The proof of this is furnished in 

 the above analysis ; and as bone-ash can be bought at a cheaper 

 rate than fine bone-dust, it is not fair to offer for sale a mixture of 

 50 per cent, of fine bone-dust and 50 per cent, of bone-ash under 

 the name of genuine bone-dust. 



I may mention, in passing, that I analysed another sample oi 

 fine bone-dust, bought from the same maker, but earlier in the 

 season, probably at a time when there was less demand for fine 

 dust than later, when the deficiency in the supply evidently was 

 made up by a larger proportion of bone-ash. 



This sample consisted of about two-thirds of fine bone-dust 

 and one-third of bone-ash, as will be seen by inspecthig the 

 following results, which it yielded on analysis : — 



Water 9-11 



* Organic matter 21"'25 



Phosphates of lime and magnesia (hone-earth) .. 61*94 



Carbonate of lime 5'89 



Alkaline salts I'TO 



Insoluble sihcious matter (sand) 1'32 



100-00 



* Containing nitrogen 2' 84 



Equal to ammonia 3*45 



Plot IX. — iManured with 3 cwt. of superphosphate, made by 

 dissolving fine bone-dust used in previous experiments in oO per 

 cent, of oil of vitriol : — 



Produce .. 9 tons 14 cwt. 3 qrs. 10 lbs. 

 Increase .. 3 tons 19 cwt. 2 qrs. 2 lbs. 



On comparing the produce of Plot IX. Avith Plot VIIL, the 

 advantage of dissolving bone-dust in acid will appear at once. 



When analysed this superphosphate gave the following re- 

 sults : — 



VOL. XIX. N 



