101 



the weight of rubber between the two is considerable. There is no 

 point in having rollers 18" long unless you are to utilize as much of 

 this as possible. 



Washing and Dripping. 



After rolling, each sheet is washed and soaked in tepid water 

 to get rid of any protein which causes what is called " rust " in 

 sheet. I have found that without this washing in warm water, 

 sheets have a tendency to stretch " rusty " and it is consequently 

 worth doing properly. After washing, sheets are dripped till all water 

 has left them. They are hung on racks which are thoroughly washed 

 each day, the racks being designed so that each tier hangs free 

 from the drip of the one above it. The stands are in the shape of 

 an inverted V with round laths across to hang the sheets over. 

 Square timber laths are not good, as the sheets take any impression 

 very easily at this stage, and unsightly lines across the sheet 

 invariably result whei-e square laths are used. The dripping I'acks 

 should be in a sheltered position where no dust can be blown on the 

 rubber. Rolling is usually finished by 11 a.m. and sheets are ready 

 for the smoke-house by 2 p.m. 



Smoking. 



Sheets should be put into the smoke-house as soon as possible 

 after the water has all dripped off, as they do not take in the smoke 

 so well if too dry. The only reason for not putting them in 

 immediately after rolling is that water would drip from wet sheets 

 on to finished or partly finished sheets that happened to be directly 

 underneath, and the introduction of too much moisture into the 

 building would retard drying beyond reasonable limits. Racks 

 should be perfectly round and wiped over carefully before sheet 

 is hnng on them, to avoid dust getting into the rubber which 

 will not wash off if it adheres before the sheets are fairly dry, 

 and will appear as a cloudy grey line across the finished sheet, 

 where it has come into contact with the dusty surface. Sheets 

 should be turned and moved so that a fresh part is over the i^acks 

 every day for the first four days of smoking, to ensure every part of 

 the sheet getting smoke through it. The size of a sheet when 

 it goes into the smoke-house is about 30" x 15" and it comes out 

 25" X 11" so that contraction reduces the square measurement of 

 a sheet by about 40 per cent. It is essential for good smoking 

 that this should not take place too rapidly, and for this reason I 

 believe in slow drying and smoking. Rapid drying closes the 

 sheet against a thorough permeation of smoke and I give 19 to 20 

 days slow smoking before I consider the sheet is finished, the 

 temperature being kept low and too much up-draft avoided. If a 

 building is of corrugated iron the smoke gets through the joints in 

 the roof quite fast enough, and there is no necessity to have funnels 

 to improve the current. My smoke house is a 60 feet by 30 feet 



