The desire for sweet substances seems to be universal in man and is not uncommon in the lower animals. The name sugar was at one time given to substances having a sweet taste, as sugar of lead, etc., but was later restricted to certain oxy-aldehydes and oxy-ketones, having the general formula C1(H2O)m which occur in the vegetable and animal kingdoms. The chief substances of this class from a chemical standpoint (see pp. 15-18) are: Cane sugar (C12H22O11).

Glucose (C6H12O6).
Fruit sugar (C6H12O6).
Lactose (C12H22O11+H2O).
Mannite (CHS)(OH)..

The important sources of sugar in nature are the sugar cane, sugar beets, sorghum or Chinese cane, sap of sugar maple trees, date palm trees, sap of ash trees of southern Europe, the bamboo, honey, raisins and milk of mammals.

History

The ancients were familiar with honey as the chief representative of this class of foods, although they also used sweet fruits. The first true sugar was prepared either from the juice of the bamboo or that of the sugar cane, and was probably first known in India. It was very early introduced into China; the sugar cane was also cultivated in the valleys of the Euphrates and Tigris Rivers.

The Story of Sugar-Surface, p. 15.

At first sugar was used as a medicine, but gradually came to be regarded as a luxury, and was partaken of only at special feasts. From Arabia through Egypt and finally by the Moors, sugar cane was introduced into Spain and the countries north of the Mediterranean Sea. In the fifteenth century cuttings were sent by the King of Portugal for planting in the Madeira and Canary Islands. From the latter country the sugar cane was introduced into Brazil early in the sixteenth century, and then into the West Indies, principally into San Domingo. It was not introduced into the American Colonies until 1750 at which time an unsuccessful attempt was made, to make sugar, in Louisiana. In 1791, however, the sugar boilers were more successful. The "ribbon or purple" cane, which was better adapted to the soil and climate of Louisiana was introduced in 1820 and since that time it has been the variety most extensively grown.

More recently new varieties have been introduced principally from Demerara. These seedlings have been grown originally from seed produced by the cane, each seed being selected and numbered. The results of growing each seed are carefully watched, poor stock is discarded, and promising canes propagated for different qualities, until those most suitable to different conditions of climate, and general environment are produced and ready for distribution.

It is interesting to note that about the time America was discovered sugar cost $275.00 per hundred weight in London, while four hundred years later, so great have been the improvements and so large is the production, it can be sold in normal times at less than $5.00 per hundred weight. Different countries successively have dominated the sugar industry. Spain and Portugal were the most prominent in the sixteenth century, then Antwerp was the center of sugar refining, and following 1585 London was the center of the sugar market. In the early part of the seventeenth century more than half of the world's sugar was produced by the use of slave labor, in Cuba, Porto Rico, Brazil, the French Colonies, Dutch Guiana and Louisiana.

The use of the beet for sugar making dates back to the experiments of Marggraff, a chemist in the University of Berlin,' who in 1747 was able to extract from beets only 1.5 per cent. of sugar; fifty years later Achard his pupil only extracted 3.0 per cent. This industry was greatly stimulated by Napolean I, and in 1806 a bounty was offered by the French government for sugar produced in France. In 1812 the production had increased so that 1650 tons of beet sugar was placed on the market; and the annual output of Europe in 1912 was over 8,000,000 tons. The raising of beets for the manufacture of beet sugar has become an important industry not only in France, but in Germany, Austria, Holland and America. The amount of sugar in the beet has been steadily increased by seed selection, better cultivation and adaptation to soil and climate until now it is not uncommon to find beets containing from 15 to 23 per cent. of sugar, although the average as produced in the United States is not more than 13 or 14 per cent. The beet is really richer in sugar than the sugar cane of Louisiana, which does not average more than 11 or 12 per cent. of sucrose.

Both cane and fruit sugar are found in numerous fruits; but the latter is the more abundant. Pineapples, contain 11.33 per cent. of cane sugar, strawberries 6.33 per cent., apricots 6.04 per cent., apples 5.28 per cent. (See table, p. 209.) These fruits it is true are not adapted for use in making sugar, but the sugar is available, as will be seen later, for the production of alcohol and vinegar.

Cultivation of the Sugar Cane

The sugar cane (saccharum officinarum), which belongs to the family of grasses, grows best in a sub-tropical climate where the plant is not in danger of being killed by an early frost, as it is very susceptible to a low temperature. It is most successfully cultivated in Cuba, the West Indies, Louisiana, the Philippine and Hawaiian Islands, Java, and Brazil. Although cane may be raised 1 Loc. cit., p. 110.

where the mean temperature is not below 66° F., it flourishes best at a mean temperature of from 75° to 77° F. It should also have abundant sunshine and moisture. In fact, cane grows best where there is at least 50 inches of annual rainfall and where half of this comes in the growing season in the late spring.

As a large amount of mineral and nitrogenous food is needed for this crop it is evident that even the best soils will ultimately be exhausted. This may be largely obviated by a careful rotation

of crops, and the growing of peas, beans or clover which by their "nitrogen-fixing" roots help to restore the fertility of the soil.

The cane is propagated by cuttings which are best put in rather late in the fall. It is necessary to cultivate the cane thoroughly during the first months of the growing season, but later the ground is shaded by the crop so that the weeds do not grow so readily. As the cane matures the lower leaves are shed, and the joints change to a reddish color, especially in the purple variety. Late in the autumn, after the mature cane is cut, the young cane sprouts anew from the old roots. In the U. S. two

crops are profitably gathered from one setting, and then new plants must be started. In many tropical islands, however, the sprouts from the old roots are cut year after year until the plants die, but profitable cultivation is only for from five to seven years from one planting. The cane is generally cut by hand labor, and is then hauled to the mill. (Fig. 15.) This hauling on the larger plantations in the United States, is done by means of special cars on a dummy railroad. The average cane production in the United States is 18 tons per acre. In tropical countries good cane contains from 15 to 18 per cent. of sucrose2 and the extracted juice, contains under favorable conditions 17 to 18 per cent. of sugar. About 95 per cent. of the total sugar can be profitably extracted in the modern mills.

There is a particular stage in the growth of the cane in which it is said to be ripe, or to reach its maximum of sugar content, then as inflorescence proceeds the extractable saccharine matter decreases. It is therefore of importance to cut the cane at just the right time. In tropical countries cane does not reach its full growth or ripest stage under twelve to fourteen months. To extend the cutting season over as much time as possible, the cane is planted at different times during a series of weeks, and in the following season, harvested in the same approximate rotation.

In Louisiana, the life of the cane is shortened by cold weather to a total of not over nine months and in consequence, its sugar content is lower than in the tropics. A temperature of 28° F. will kill the cane and thus prevent further growth, and the deterioration of the crop after the frost is immediate.

MAKING CANE SUGAR

There are two general processes for obtaining the juice in making sugar; (1) by grinding or crushing the cane, and (2) "diffusion." The former process is the one usually applied to sugar cane, and the latter to sugar beets.