OUR contemporary, La Nature, devotes an article in a recent number (December i) to a consideration of the use of substitutes for sugar, in view of the present shortage of that commodity. Sugar is a foodstuff; but as a nutrient it can be replaced by other carbohydrates, such as those contained in farinaceous foods and vegetables. The essential thing as regards sugar is to find a substitute with sweetening properties. Glucose, obtained by hydrolysing starch with sulphuric acid, is the only sugar other than the ordinary supplies producible in large quantities; but it has a low sweetening power, is not economical, and has reached an almost prohibitive price in France. There remain the sweet chemical products, of which the two chief are dulcin and saccharin. Dulcin, para-ethoxyphenyl urea, is obtained from phenetidine and urea, and has about two hundred times the sweetness of cane-sugar. It has not, however, been much used as a sweetener, since saccharin is cheaper and much more effective. This compound, it may be recalled, has for its parent substance toluene-the coar-tar product which serves also to provide the explosive trinitrotoluene. In making saccharin, toluene is converted first into its sulphochloride and then into the sulphon-amide, which is oxidised with potassium perman ganate to produce orthosulphamidobenzoic acid. Saccharin is the anhydride, or imido-derivative, of this acid; it is claimed to be about five hundred and fifty times as sweet as cane-sugar. It is not very soluble in water, and is generally employed in the form of its sodium or ammonium salt (sucramine), both of which are readily soluble.