364 
Cultivation and Management of Hops. 
aperture at tlie base of the cowl were matters of no calculation 
or consideration. In the modern kilns the hair-level is, at least, 
13 feet from the fire, and in all these buildings, whether circular 
or square, the relative proportions, length, and width of the various 
parts, are carefully observed. It has been ascertained by scientific 
researches as to the weight, velocity, and desiccating power of 
heated atmospheric air, and confirmed by experience, that the 
height of a circular kiln above the hair should be one and a half 
times its diameter at the hair-level, and that the opening at the 
summit for the egress of air should be one-seventh of the same 
diameter. It is also calculated that, according to the present 
method of drying hops, apertures for the admission of atmospheric 
air should be judiciously arranged and carefully regulated in the 
lower part of the kiln under the hair, upon the following scale, 
viz. : (i feet of aperture (superficial) for a 16-feet kiln, S feet of 
aperture (superficial) for an 18-feet kiln, and so on, in order that 
the greatest possible amount of moderately heated air may pass 
quickly through the hops. Hops were formerly stewed dry by 
concentrating stove-heat upon them. Now the great object is to 
desiccate them — to drive off their moisture — by a process as 
nearly resembling the action of the sun and wind as can be suited 
to the circumstances. 
Hops while stewing, according to the old receipt, give out a sweet 
odour, which may be smelled a long way to leeward of the oast. 
This escape of essential aroma, once hailed with delight as satis- 
factory evidence of the good qualities of the hop, is deprecated 
and avoided by growers of the present day. It is understood that 
the temperature to which hops should be subjected ought not to 
exceed 130^ : beyond that point it is generally admitted that a 
serious loss of essential principles occurs. In the opinion of those 
who have studied the question, a mean temperature of 110° 
Avould be far better ; but the brewers do not recognise the increased 
value of samples so treated by giving a corresponding increase of 
price, and the expenses of such management being nearly doubled, 
it follows that the practice of drying two loads in twenty-four 
hours, at or about a heat of 130"^, is universal. The circular is 
the most usual form of kiln, as it occupies less room, while it 
affords more available space than any other shape. Air apertures 
may be more easily arranged, and there is not so much resistance 
to the circulation of air as in square kilns, which are preferred 
by some, because they may be converted into cottages or like 
useful buildings. Some prefer an inner circle or chamber ; others 
hold that it is superfluous. According to the usual mode of 
drying at a high temperature, the inner chamber or circle has 
many advantages, as it diminishes the loss of heat by radiation, 
at the same time confining it and concentrating its action. For 
