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occasioned by the failure of the tail pump (sirup) of the triple effect, in 

 several instances, materially reduced the yield of sugars per ton of caue. 

 Thispump, after repeated failures, was removed and one of greater power 

 was arranged for this service, but it also proved unequal to the work 

 required. A third pump was built especially for pumping the sirup 

 from the triple eftect, and fortunately occasioned few delays. The diffi- 

 culty seemed to be due to the very small amount of sirup to be removed 

 from the apparatus in proportion to the size of the pump. In order to 

 obviate this difficulty the builders of the machinery suggested and tried 

 pumping back a part of the sirup into the juice tank and thus obtaining 

 a greater volume of liquor for the pump to work upon. As far as the 

 pump was concerned this plan worked fairly well, but from a sugar- 

 making point of view it was far from successful. It is obvious that in 

 this method of working a part of the sirup may be retained in the ap- 

 paratus many hours and suffer deterioration. That this was undoubt- 

 edly the case was evidenced by the large inversion which ocurred at 

 times when this method was practiced. But in this case a remedy was 

 essential to the continuance of the experiments, and this bad remedy 

 was the only one available at the time. 



The delays due to other pumps were numerous. The pump to remove 

 the sirup from the still practically failed to accomplish this work, and, 

 after vexatious delays and the loss of considerable sugar, it was replaced 

 by another, which worked only fairly well. The removal of the sirup 

 from the still was a constant source of annoyance throughout the 

 experiments. The fault was probably in the use of a pump not adapted 

 to pumping sirup heated to very nearly its boiling point. 



The construction of the still was such that sirups were heated to a 

 high temperature, which was maintained during long periods. This is 

 manifestly contrary to the maxims of good sugar-making. Apparatus 

 designed to obviate this difficulty has already been described. 



It is probable that the methods of vacuum evaporation employing 

 thin films of liquor could be successfully employed in the recovery of 

 the alcohol. The Yaryan Company have constructed an apparatus for 

 use in dehydrating wine, which they claim is successful. This appa- 

 ratus separates the alcohol and a portion of the water from the wine, 

 rejects the water and returns the alcohol to the mother liquor. The 

 alcohol furnished by this apparatus would probably be of low concen- 

 tration, but could easily be increased in strength by a second distilla- 

 tion. In this method the operations are performed in partial vacuo and 

 subject the sirup to a low temperature for a very short time. 



The filter presses were the greatest source of loss of alcohol. This 

 was not due to any fault in the press as built for ordinary sugar-house 

 worJi. For work with alcohol, the press should be so arranged as to 

 minimize losses by evaporation. In order to accomplish this a special 

 construction is necessary. All cloth surfaces should be covered, since 

 the alcohol and sirup mixture will follow the cloth, no matter how 



