THE CUBA REVIEW 21 



proper intervals, he can control within very narrow limits the size of the grain p ro . 

 duced. Evaporation is here continued until a thick, viscous, semi-fluid mass called 

 "massecuite" results, containing just enough liquor to enable it to flow from the pan 

 by gravity, as, were it left in the pan until all the moisture were evaporated, all the 

 impurities still contained in the liquor would be boiled into the sugar, making it 

 unsalable; it would be difficult to prevent burning during the final stages of evapora- 

 tion; and the grains would stick to one another and form a solid mass which would 

 have to be removed from the pan by mechanical means. When the material within 

 the pan has reached the proper consistency, the sugar boiler in attendance opens a 

 valve, admits air into the pan, and then opens a valve in the pan's bottom allowing 

 the massecuite to drop into canals leading to crystallizers from which it enters a long 

 tank with a rounded bottom called the "mixer", in which a shaft provided with pad- 

 dles is revolving. 



From the mixer the massecuite runs through spouts into centrifugal machines. 

 These are cylindrical shaped, perforated lining of the brass baskets hung on a central 

 shaft, by which the baskets are caused to revolve very rapidly, reaching as many as 

 1,000 revolutions per minute. Through the openings in the brass basket the liquor 

 is thrown out by centrifugal force, but the sugar is retained, the openings being too 

 small for the grains to pass. After the liquor has been sufficiently removed from the 

 sugar by this process, the centrifugal is stopped and the sugar caused to drop through 

 a valve in the bottom of the machine into bins, from which it is either passed through 

 drying tubes where it is more thoroughly dried by means of a current of hot air, or 

 else is passed directly to the automatic weighing machines and bagged. From here it 

 is taken by means of conveying machinery to the warehouse, where it is stored until 

 taken away to the port. 



The processes just described are carried on through machinery illustrated in the 

 case of "Cunagua" by No. 19, which shows the boiler room still unfinished, though 

 in operation; No. 20 which shows the electric generating plant, as "Cunagua" is prac- 

 tically entirely electrified; No. 21 showing the excellent view of one of the two "tan- 

 dems" or trains of mills electrically operated; No. 22 showing preheaters; No. 23 

 showing the filter presses; by No. 24 showing the two sets of quadruple effects with 

 which "Cunagua" is equipped; by No. 25 showing an excellent view of the crystal- 

 lizers into which the massecuite is draw y n from the vacuum pans shown above, and 

 the centrifugals in which the sugar is purged and whitened after being taken in from 

 the crystallizers. At the extreme right of this photograph is also seen the automatic 

 bagging scales, and at the edge of the picture the mechanical conveyor, more clearly 

 shown in No. 26, which carries the sugar from the factory across a narrow 7 passage- 

 way into the warehouse, where it is piled for storage, as showm in No. 27. 



We have mentioned only briefly the agricultural side of the sugar industry, but 

 changes have occured here that correspond in importance to those brought about in 

 the factories themselves. The first cane of the Island was undoubtedly produced on 

 lands from which the forests had been felled, and with the aid of only the cane knife 

 or "machete" and the hoe. This system is still employed in those parts of Cuba 

 where virgin forest abounds, and is practically the most economical and satisfactory 

 method of producing sugar cane, as when planted on fertile virgin soil of this char- 

 acter, the cane stools ratoon and produce crops for many years without the necessity 

 of new plantings. Unfortunately, however, many years ago the three western 

 Provinces were practically denuded of their forests, with the result that cane now 

 must be planted on more modern lines on lands which have been prepared by plow- 

 ing and harrowing, and the weeds which always follow agriculture must be held in 

 check by cultivation. 



The first plows to be used in Cuba were beyond a doubt composed of crooked 

 sticks and doubtless were without a metal point of any description. At a later date 

 the rounded metal instrument with extended point was added, and a means of lower- 



