168 ANNUAL OF SCIENTIFIC DISCOVERY. 



formed entirely different from the original. That water should have 

 this effect, it is necessary that it should come in contact with the air, 

 and that it should encounter ad dissolve certain fermenting sub- 

 stances which are found in the tissue of the bitter almonds, with the 

 amygdaline. 



" The rapidity with which the cane juice, in warm climates, under- 

 goes alteration, is the great obstacle to the extraction of the pure solid, 

 and the great cause of loss in the process. The chemist, in his labo- 

 ratory, solves the problem of the extraction of sugar, by the employ- 

 ment of alcohol. This agent, without producing the slightest alteration 

 in the properties of the sugar, separates it from its associated substances, 

 and protects it from every destructive influence. Alcohol, however, will 

 not answer the purposes of practical industry, which require the em- 

 ployment of an agent low in price and of easy application. Such an 

 agent alcohol is not ; it is costly and dangerous as a combustible. But 

 is it beyond the resources of chemistry to discover a liquid which, like 

 alcohol, will separate the sugar and prevent the fermentation which, in 

 the manufacturing processes now in use, ensues as a consequence of the 

 contact of the juice with the external air? Such \>as the question 

 Melsens proposed to himself, and which he has answered triumphantly 

 by the production of the agent. 



" It was step by step, by an infinite series of experiments, and by 

 the concentrated direction of a thoughtful and educated intellect, that 

 Melsens succeeded in detecting and bringing to the light of day what 

 had escaped the scrutiny of Dumas and Berzelius. The first small 

 fact upon which he proceeded was, that, in the tissues of the cane, 

 sugar is found dissolved in water, and it will remain there in a state 

 of preservation for a considerable length of time. From this fact, it 

 was legitimate to infer, that if water could be used as a solvent, the 

 conditions accompanying its presence in the tissues being retained, the 

 saccharine substance could be extracted unaltered. The difficulties, 

 therefore, attending the extraction are not connected with the sugar or 

 the water, but with the air, and the fermentatives which its contact 

 develops. This being the case, were it possible to crush the cane in 

 xacuo and to express the juice and boil it in xacuo, either for the pur- 

 pose of purifying or evaporating, nothing would remain to be desired. 

 But this is not possible, at least upon a large scale. Melsens was 

 thus urged to the discovery of an agent absorptive of air, hostile to 

 fermentation, innocuous to man, low in price, and easy of production. 

 Such an agent he found to exist in the bisulphite of lime. 



" Melsens' experiments with this agent were made upon a dozen 

 varieties of juice, including beet-root juice, or pulp, grape juice, 

 and cane juice. The results were uniform ; the sugar crystallized 

 without loss, without trouble, and without the production of molasses. 

 The earlier experiments demonstrated that the bisulphite of lime, em- 

 ployed as a body absorptive of oxygen, and as an antiseptic, had no 

 injurious effect upon the sugar, if applied cold, and in such a manner 

 as to mix with the juice at the very moment of the rupture of the 

 cellular tissues; and further, that in its presence the action of heat 



