CANE SUGAR. 



between the results. The experiments in question were planned by Maxwell to 

 determine the relative demands made on a soil by different varieties ; the weight 

 of cane, including its stalks and waste products and the weight of ash therein 

 was determined ; this observation combined with the anaylsis of the ash gave 

 data for the construction of a detailed balance sheet. The results of a second 

 season's determination gave, however, results quite at variance with those 

 obtained in the first. I do not then think that any very useful purpose will be 

 served by quoting in full these and similar analyses. 



Reviewing however the analyses due to Maxwell, Eckart, Boname and 

 others, the following statements can be made : 



(a.) By far the greater part of the ash of the entire plant is contained in 

 the leaves, tops and waste matter; such is especially the case in Hawaiian, as 

 compared with Guadeloupe, canes. This relation will be profoundly affected by 

 the personal equation of the investigator as well as by conditions of growth and 

 period of harvest. 



(l.J In the leaves and waste matter the predominant element is silica, 

 with potash second in amount ; in the stalks the position is reversed. 



(c.) The lime and magnesia are present in approximately equal amounts, 

 sometimes one and sometimes the other being in excess ; the same statement 

 is true of phosphoric acid and sulphuric acid. 



(d.) The quantity of nitrogen and ash contained in the entire Hawaiian 

 grown plant, per ton of stalks, is much greater than in the Guadaloupe canes ; 

 the yield per unit area is much greater in the former than in the latter, the 

 growth in Hawaii having taken place under heavy manuring, aided by copious 

 irrigation. This does not imply a greater drain on the soil, since the leaves 

 and waste matter are returned to the soil and most of that carried away to the 

 mill in the stalks is still available. 



(*.) The ash of the entire plant lies within the following limits: 

 Silica 45 per cent, to 50 per cent. ; potash 15 per cent, to 20 percent. ; lime 

 4 per cent, to 6 per cent. ; magnesia 4 per cent, to 6 per cent. ; phosphoric 

 acid 2 per cent, to 5 per cent. ; sulphuric acid 2 per cent, to 5 per cent. ; 

 in some instances comparatively large amounts of chlorides have been found, 



The Amount of Ash contained in a Crop of Cane. 



In view of what has been written above, it at once follows that any attempt 

 to obtain a general balance sheet of plant food demands is fallacious ; dependent 

 on which series of analyses is taken, results varying several hundred per 

 cent, may follow. Thus in one extreme case in Hawaii 94 Ibs. of ash were 

 obtained per short ton of stalks, a figure falling to 15 Ibs. in one of Boname's 

 trials in Guadeloupe. 



The Ash of a Plant in Relation to Manuring. It has been 

 thought that the analysis; of the ash of a plant and the agricultural balance 



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