Hop Cultivation. 
255 
the cold draughts do not mingle with it directly and diminish 
its heat. Upon the floor of joists or oast laths horsehair cloth is 
nailed to prevent the hop dust from falling through, and to 
keep the hops from burning (fig. 10, a). 1 
Welsh anthracite coals are genei’ally used for drying. Coke is 
mixed with these coals by some planters. In Worcestershire and 
Herefordshire a good deal of coke is burnt. Charcoal is employed 
extensively to keep the fires going, and many dryers put much on 
the fires, as it is considered that it makes the hops soft. For 
the first hour or two the fires are ashed up and allowed to glow 
gradually, so that the heat is increased slowly. A temperature 
of from 120 to 130 deg. Fahr., and even higher, is reached, and 
must be maintained in order to dry the hops, laid at from 8 to 10 
inches thick upon the floors, in less than 12 hours, and so that 
the kiln may be loaded twice in the 24 hours. 2 This temperature, 
as has been pointed out before, is too high. The hops would 
be far better in every respect if they could be slowly desiccated 
at a temperature of from 80 to 100 deg. Fahr. But this 
would take 18 or 20 hours or more, and would necessitate a 
double amount of kiln accommodation, as the hops must be 
picked within a very short time. 
Sulphur is burned on the fires generally in all districts. It 
is put on soon after the hops are on the kilns, when they have 
begun to reek ; and again later on, when the hops are turned, an- 
other quantity is put on the fires. From 10 to 20 lb. of best 
“ Virgin roll ” brimstone are burnt for each kiln load. Sulphurous 
acid gas is generated from the burning sulphur, which has a 
strong acid reaction and has in a degree the effect of bleaching 
the drying hops. This action of sulphur is limited, as the fumes 
being driven off by the air currents cannot be properly concen- 
trated upon the hops ; but planters have considerable faith in the 
virtue of sulphur fumes for imparting a yellow colour to the cones, 
and in bleaching those that have been made brown by sun and 
wind. The application of sulphur to drying hops does not 
injure them for brewing in any way. No sulphur is retained in 
or on the cones. This process must not be confounded with that 
of throwing up powdered sulphur over the plants for mildew, 
some of which may possibly be retained in the strobiles in cases 
where sulphuring is done when these are formed. 
Two kilns of 20 feet square, or of 18 feet diameter, would 
suffice for 20 acres of hop land. These, with suitable cooling 
1 These figures of kilns and cooling rooms (10, 11, 12) were kindly drawn 
for me by Mr. Hubert Bensted of Maidstone. 
2 As a rule, kilns are loaded about noon and midnight. 
