ii6 PLANT PRODUCTS 



The Date Palm is also one of the minor sources of 

 sugar. Most species of the palm can be used for the 

 production of sugar ; many of them are used for the 

 production of sugar for fermentive processes. When it is 

 desired to manufacture sugar the palm is cut, and the sugar 

 juice runs into a pot. The pots are collected, and the juice 

 quickly boiled down before fermentation takes place. With 

 the aid of a hand centrifugal machine very pure sugar can 

 be obtained in a simple manner. The quantity made is, 

 however, small, and can never compete commercially with 

 the other sources of sugar. 



Sugar Refining. — ^Most of the sugar industry in the 

 British Isles in the past has rather turned on the purifica- 

 tion of crude sugars produced elsewhere. Many reasons 

 have been given for the collapse of the sugar purification 

 industry in the British Isles. If reference be made to an 

 old work by Higgins, dated 1797 (see Bibliography), the 

 following will be found : " It is now well-known that an 

 artist with a very little education will soon learn all that 

 is useful to him in mechanics and chemistry." If such 

 opinions were generally held, the collapse of the industry 

 is readily understood. 



Turnips, etc. — A very large amount of sugar is 

 produced and consumed in the form of swedes, turnips, 

 and mangolds. These crops form the essential part of a 

 rotation, and permit the cleaning of the land. Good seed 

 beds and liberal manuring are essential, and the land is usually 

 worked into ridges. Super-phosphate, sulphate of ammonia, 

 and potash salts are all used as well as farmyard manure. 

 For mangolds, salt is needed as well. The seed is generally 

 used somewhat generously, the young plants being " singled," 

 that is to say, all those that are not needed are hoed out. 

 In the United Kingdom, about twenty-four million tons of 

 turnips and swedes are grown. The swede crop in the 

 northern counties contains about 6 per cent, of sugar, on the 

 average a little more. The average for the whole country 

 is probably slightly less, and the white turnips will be 

 distinctly lower, but it is probably not seriously wrong if 



