Dr. A. Schulte im Hofe 113 
dried very unevenly and the cost of fuel was 
comparatively great. Probably it is for these 
reasons that such drying-barns are not more 
extensively used. 
In 1903 the method of drying the cacao 
on heated stone platforms was introduced on 
several plantations in San Thomé. Heated 
air from a furnace is conducted under a plat- 
form 5 m. (16 ft.) long by 2 m. (6 ft. 6 in.) wide, 
made with the sides raised about 25 cm. (10 
in.). The cacao is dried on these platforms 
in fairly thick layers, being frequently turned 
during the process.. I have been unable to 
find out any particulars as to the results 
obtained by such a method. 
When in Fernando Po in 1899, I saw on 
three of the plantations a primitive method 
of drying by means of tunnels,’ ro m. (32 ft. 
gin.) long by 2 m. (6 ft. 6 in.) wide, and 
1°75 m. (5 ft. g in.) high. These were heated 
by two pipes running along the floor through 
which the heated air was conducted from a 
furnace at one end of the tunnel. In each 
side-wall there are ten doors, each 1 m. (3 ft. 
3 in.) wide ; through each of these, eight trays 
can be pushed and placed on ledges, one over 
the other. The total area of the trays is 
150 sq. m. (180 sq. yd.). Since there is but 
very little circulation of air in these’ tunnels, 
the distribution of heat is very unequal. The 
* Some think the latest ‘tunnel’ systems will be 
freely adopted in the future—H. H. S. 
8 
