NORTHERN SUGAR INDLSTRY. 



21 



cose, 2.75 per cent, other sugars and 2 per cent, solids not sugar. Add- 

 ing together the anoptose and non -saccharine solids, get 4.75 per 

 ceut. This will prevent au equal quantity of sucrose from crystallizing, 

 and there will be left of sucrose 10—4.75=5.25 percent. Deduct the 5 

 per cent, lost in evaporation and there is left 4.75 per cent, of sugar 

 which can be obtained in marketable form. This is calculated on the 

 weight of the juice, and. for the weight of cane must be divided by two. 

 The percentage of sugar obtainable, therefore, based on total weight of 

 cane worked, is only 2.37 or 46.4 pounds per ton. 



I doubt whether any factory in the country this year working sor- 

 ghum cane exceeded that yield on the whole amount of cane worked up. 



In the cane worked at the Department of Agriculture during the past 

 season the average analysis of the juices was — 



Sucrose.... .percent.. *8. 84 



Other sugars do 4.00 



Solids, not sugar (a li ttle less thau ) do 2. 00 



Five per cent, loss do 42 



Available sugar do 2. 42 



Yield of juice do 42. 00 



Available sugar per ton pounds.. 20. 30 



This was almost the exact quantity obtained save from 5 acres of 

 cane raised in Indiana, which gave over 60 pounds per ton. At Rio 

 Grande the percentage of juice extracted was 47f ; the sucrose was 

 9.75; other sugars and total solids not given. 



At Champaign,! III., the percentage of juice expressed was 60; per- 

 centage of sucrose, 7.78; percentage of other sugars, 4.70; specific 

 gravity, 1.0591. 



COEFFICIENT OF PURITY. 



There is another method of expressing the ratio of sucrose to other 

 substances present In saccharine juices which is more convenient but 

 less accurate than the number expressing available sugar. It is gener- 

 ally used in the beet-sugar countries, and for rich juices is near enough 

 the percentage of available sugar for practical purposes. 



The " coefficient of purity" is the ratio per cent, of the total sucrose in 

 a juice to the total solids. Thus in a juice containing 14 per cent, total 

 solids and 10 per cent, sucrose, the figure for purity coefficient is 71.5. 

 Really, in this case only 60 per cent, of the sucrose present is available, 

 and hence the purity coefficient number is too high for available sugar. 



In a case, however, where the sucrose is only half the total solids 

 (which often happens with sorghum juice) the purity coefficient would 

 be 50, while the available sugar would be 0! 



During the past season the juices worked for sugar at Washington 



* lu the juices worked for sugar. 



+ Double milling. This uumber is the average of the numbers given by the super- 

 intendent. (See letter of Mr. Hughes, p. 60.) 

 t See letter from superintendent, p. 62. 



