106 



served to strain or filter the cider almost perfectly. This was observed 

 ill an English factory where the must was fermented in open " keeves," 

 the head being- skimmed oil' until active fermentation had sul)sided, 

 and the product being then run through this iilter and put into casks 

 for ripening. This apparatus does good work, hut the cider is much 

 exposed to the air. 



Tlie cellvJoge pov^er filter. — Some of the English makers have come 

 to use the German filter shown in ligurc 21. This is made by Otto 

 Fromme at Frankfort, and is the liest device observed. It is, how- 

 ever, costly, and a force pump is required to di-ive the liquid 

 through the filter, or the liquid must be drawn from some height in 

 order to give the necessary pressure. This is also a wood pulp or 

 cellulose filter. The pulp is arranged between perforated disks, and 

 the machine permits of dismounting and washing the parts and the 

 pulp at will. In some English factories attempts were made to filter 



Fig. 24. — Cellulose power filter used in Germany. 



the fresh juice with this machine, but this generally resulted in fail- 

 ure, and besides was very wearing on the apparatus. Fresh apple 

 must is very difficult to filter because of the pectose or mucilaginous 

 substances it contains. The use of any of the above filters does not 

 appear to l^e practicable except when the must has been fairly well 

 fermented, and has freed itself in this manner of a large part of the 

 parench3'matous tissues and albuminous matters present therein. 



Ashestos md' fiJter. — The French use a filter (fig. 25) which they 

 claim will remove all insoluble matters from the fresh must, and leave 

 it clear and limpid as it goes into the cask. No demonstration of this 

 was seen, ]>ut this filter (Filtre Maignen) is much used in France, 

 and appears to be a good, cheap filter. It is made from asbestos. 

 A fairly closely woven asbestos sack, 10 or 12 inches in diameter and 

 of anv desired length, is tied tightlv at one end; tluMi in tlie bottom of 

 this is placed an openwork disk, and a string is tied al)ove the same so 

 as to nearly draw the sides of the sack together; a))ove this is placed 

 a second disk; and so on until the filter sack is filled. The open end 



