i/6 The Fermentation of Cacao 



Also, it is difficult to keep such a surface clean 

 and free from larger insects, cockroaches, &c., 

 &c. In considering what acid-resisting smooth 



o o 



surfaces could be substituted for wood, the 

 writer has passed over such materials as 

 glazed earthenware, enamelled iron and 

 " Ruberoid " in favour of planed slate. In 

 order to test the properties of this material 

 he constructed a slate sweating box of i in. 

 planed slate with sloping floor and liquor 

 exit. It was rather elaborately made with 

 rounded corners and acid-resisting cement for 

 joints, and was consequently more expensive 

 than it need have been. However, planed slate 

 in slabs is not an expensive material : I refer 

 to the sort of thing supplied for old-fashioned 

 public urinals. I have carefully experimented 

 with this box, contrasting temperatures with 

 wooden boxes, and am quite satisfied that in 

 slate we have an ideal surface to make perma- 

 nent linings for the interior of concrete sweat- 

 ing boxes in place of the loose wooden 

 casings now used on most large cacao estates. 

 Litharge mixed with liquid glass solution 

 makes a suitable cement for joints. Possibly 

 -J-in. or f-in. thick slabs would serve under 

 these circumstances, but I am afraid slate 

 would be too heavy and breakable a material 

 for the sliding up partitions between the 

 boxes ; however, the lower 18 in. of this inter- 

 rjartition should not be removable and could 

 be made of slate while the upper part could be 



