Some recent improvements in. the process of making and purifying sugars consist in applying to the juice a saturated mixture of alum and lime, in the proportion of two pounds of the mixture to a hundred gallons of the juice. These being intimately mixed, the acid is to be neutralized by the application of milk of lime, in the proportion of three pounds to a hundred gallons. If there be an excess of acid, it will be discovered by the application of the test paper usually employed by chemists to detect acids, and more milk of lime must be added ; and if there be an excess of alkali, it may be discovered by the application of the test paper used for detecting alkalies, and more juice must be added. When the mixture ceases to affect either the test for acid or alkali, the impurities will be precipitated, and may thus be separated ; and the juice thus purified is to be subjected to the usual mode of clarification and concentration. Pure raw sugar is now obtained direct from the sugar cane, without having undergone any subsequent process of decolor-ization or refining, prepared by effecting the last stages of the concentration of the cane juice in a vacuum, at a temperature insufficient to produce any chemical changes in its constituent parts. By this improved and scientific process of manufacture, no molasses or uncrystallizable sugar is formed, and there is, hence, an increase of 25 per cent, in the quantity of sugar obtained. Literary Notices* THE KNICKERBOCKER TNE for January, 1858. John A. Gray, New York__This, the oldest of American monthlies. in commencing its fifty-first volume, starts well. " The Life of a Midshipman" is still continued, and seems to increase in interest as it progresses. A good sketch, entitled " John Bradshaw's Ad- eh r. Edito:'sTaWe"iscovered\vith alltherich of library lore for the past month ; and rieht pasantly does the editor carry the reader through these realms of printed thought, giving information, cautions and advice by the way, f regu p with that at-tenticn they deserve, l rot Jie iltogeer powerless in forming the future literary mind of our country. The criticisms are just, and a just criticism is worth a volume of praises to a young or even old author. THE ECLECTIC MAGAZINE.—W. H. Bidwell. Editor and Proprietor, New York. We have received the January number of this excellent periodical. It contains a portrait of Mrs. Barrett Browning, the poetess, and a picture representing Sir Waiter Scott and his lite-raryfrienda atAbbotsM. a are well chosen, asfoirrepretn lives ofthe kd ofsel(ic DS Hiatal be made throughout the year. It is one of* the best magazines published in our country, and we wish it for the New Year all that success it sowell deserves. BLACKWOOD'S EDINBURGH MAGAZINE.—Leonard Scott & Co., New York. This number contains an excellent article entitled "Phrenology in France," in which it adducesmany insncs of remarkable exceptions to the laws of" this system, and asks the phrenologists not to explain, but to refute them. There is also an article on the " Religions of India," and many others equally interesting. AMERICAN FARMERS' MAGAZINE.—J. A. Nash, Editor and Proprietor. No. 7 Beekman street, New York. This highly interesting and valuable periodical has entered upon its eleventh volume. and contains much matter that will interest the farmer, mechanic. and aU who have the beauties of nature around them, and wish to know how to improve natural advantages by cultivation. CHARLESTON MEDICAL JouRNAL AND KEVIEW.-J. D. Burns, M. D., Editor and Publisher. This bi-monthly io e r o has (hanged its editoi, d ems from fee Janua number to be as ful of valuable information in the medical science as ever, if not more sc. THE NORTH CAROLINA JOURNAL OF EDUCATION__ No. 1 of Vol. 1 is received. It contains an excellent article entitled " The Bible as a School Book," in which the writer urges weighty reasons in its favor. We hope never to see the 'Vord of God banished from its proper place as the first of all books as an educator of youth. It is a priceless gift to man. THE YOUNG MEN'S MAGAZINE for January, published at 348 Broadway, New York, by R. C. McCormick, is an excellent number for the young men of our conu and deserves to be widely circulated and carefully read.
This article was originally published with the title "Sugar-making" in Scientific American 13, 19, 152 (January 1858)