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MONTHLY JOURNAL OF AGRICULTURE. 



body lias yet effectually succeeded. Let me ex- I 

 plain my meaiiiug : 



If you cut in two a sugar cane and examine 

 the interior part of it with a magnifying glass, 

 yon perceive the crystals of sugar as distinct and 

 as white as those ol double refined sugar. The 

 object of the operator should be then either to 

 extract those cry.stals without altering their 

 color, or. if that be found impracticable, to .sepa- 

 rate them from the impurities mixed with them, 

 while the juice is in its natural state, and yet 

 contains but little coloring matter. Instead of 

 this, the juice is limed whi'e all the impurities 

 are in it. In separating the feculencies from the 

 juice and uniting them in large flakes, lime dis- 

 solves a portion of them and forms with them 

 coloring matter which, we all know, at once 

 discolors the juice, when lime is u.sed in excess. 

 Afterwards lieat is applied, either in clarifiers* 

 or in the grandi' ;t but most of the impurities 

 foimd in the juice will decompose and bum at a 

 degree of heat far below the boiling point, say 

 at a hundred and twenty degrees of Fahrenheit. 

 This is shown by the thick scales continually 

 forming in the grande. From that degree of 

 heat the decomposition goes on in the clarifier, 

 till the juice is drawn, and continues in the 

 prandc so long as there are feculencies left. — 

 This decomposition greatly increases the quan- 

 tity of coloring matter, so that, as the juice is 

 being clarified, it loses in color what it gains in 

 purity: and here, let me show the relative value 

 of the grande and of clarifiers as agents of clar- 

 ification. In the grande, if it is well attended 

 to, the skummings are taken up as fast as they 

 rise. A portion of them is removed before they 

 begin to decompose, and the process goes on, 

 so that, before the juice reaches the boiling 

 point, nearly all the feculencies are removed and 

 the source of coloring matter is removed with 

 them. 



Clarifiers reach the boiling point much quick- 

 er and cannot easily be skummed. The general 

 practice is, to bring them to that point without 

 skumming ; to let the feculencies separate from 

 the juice by cooling and by rest, and to wash 

 out the clai-ifiers everj' second or third time they 

 are filled. Heat and alkahes acting in them 

 upon the accumulated feculencies of one, two, 

 or three charges, dis.solvem much larger portion 

 of those feculencies than they can possibly do 

 in the grande ; the fonnation of coloring matter 

 continues during the time of rest, and, accord- 

 ingly, planters, after repeated trials, generally 

 agree that juice well clarified in the grande has 

 a brighter and a lighter color, and makes better 

 sugar than that obtained from clarifiers. 



But to return to my subject, the first object of 

 research should be, to find means of clarifying 

 the juice, without creating coloring matter. It 

 is said that presses, something like those used to 

 repress cotton here, have lately been successful- 

 ly employed in the \A'^est Indies, instead of 

 rollers ; tliat the juice obtained is mu- h purer, 

 and that a nmch larger quantity of it i« extract- 

 ed from the cane. If so, this will be a great im- 

 provement, and the first step of the process I 

 ■would recommend. From juice thus obtidned, 

 or even from our oviii, I have no doubt that all 

 impurities less soluble than itself, may be sepa- 

 rated by mechanical means, before heat and al- 

 kalies are applied, or at least with a vei-y small 



* Clarifiers are isolated pans in which the juice is 

 gometimes clarified. 



iThe grande is the evaporator failhest removed 

 from the fire iu Compound funiaces. 



(286) 



quantity of alkalies. All other liquids, all fatty 

 substances and oils, except cotton seed oil, are 

 clarified by very rapid process. Cane juice can 

 no doubt be clarified by similar meau.s, and if 

 this was accomplished, the process of sugar 

 making would be very much simplified. The 

 clarified juice might then be placed in an open 

 evaporator, heated by the waste steam of the 

 engine ; then be limed and skiinmed if necessa- 

 ly, and concentrated to fifteen or si.xteen degrees 

 of the 'pcse sirop ; then purified by filtration 

 througli animal charcoal, if white sugar was 

 wanted, or by rest for other qualilie.s, and finally 

 concentrated in vacuum pans of great power, 

 such pans as Mr. Thomas A. Morgan now uses 

 and which he tells me can only be made in 

 America. 



The superiority of the vacitum pan is not uni- 

 versally admitted, and we are told that in France 

 it is superseded by open jians, similar in con- 

 struction to those called here Mape's Evapo- 

 rators. However this may be, I cannot help 

 believing that the vacuum pan has many decided 

 advantages over all others ; one is manifest ; 

 the sugar may be grained in the pan, and the 

 granulation is completely under the control of 

 th.e operator. He may accelerate or retard it 

 at pleasure, he may carry it so far that sugar will 

 not run from the pan, and will have to be taken 

 out of it ; he may so conduct the operation as to 

 increase almost at will, the size and hardness of 

 the crystals. This last is an indispensable requi- 

 site, if the pr.ictice of draining sugar in pneu- 

 matic pans .should be adopted. The atmospheric 

 pressure is much too powerful for sugars boiled 

 in any other manner; it breaks and desti'oysthe 

 crystals, and in a very few days sets the sugar 

 to fermenting. 



The pneumatic draining of sugar has many 

 thuigs to recommend it ; the usual loss by drain- 

 age is avoided, sugar is got ready for market 

 day -by -day, as it is made, and it may be bleached 

 by pouring white syrup over it and forcing it 

 through the mass. It is said tliat the process is 

 attended with considerable lo.ss in weight; but 

 as all that drains from the pans mtiy be boiled 

 over once or twice, it is not easy to conceive 

 how the loss can occur. 



One observation on the subject of our build- 

 ings. Houses of uubunit bri(-'k are of late much 

 recommended to the working classes at the 

 North, and to the settlers in the prairie.s, as being 

 cheaper, drier and healthier than those built of 

 brick or stone. On reading the description of 

 those buildings, in the excellent Report of the 

 Commissioner of Patents, it struck me tiiat they 

 w ere substantially the same as the old houses of 

 Louisiana, known by the name of liouses eri co- 

 lo'inhage. Is it not owing to a change in our 

 mode of building that the present race of our 

 people is not so hardy and as long lived as their 

 ancestors were ? In former days no one ever 

 entered one of those ancient hou.ses without 

 finding in it a brace of octogenarians, at least. — 

 With our old houses, old people seem to have 

 disapiieared ; and to you and me. Sir, wlio are 

 not (juitc as young as we have been, it may be 

 of some consequence to ascertain the cause of 

 this phenomenon. I have no doubt it is in a 

 great measure owing to the dampness of our 

 modem dwellings, and ihouijh we may not per- 

 suade our ladies to return to the primitive archi- 

 tecture which was the pride of their great 

 grandmothers, we may at least adopt it for our 

 laborers, and I will make the trial. Tlie brick 

 houses we have built for the purpose of increas- 



