II s 



pari framed with wood. The distillation was continued for three 

 hours, and during the spring and summer months aboul 1 12 pounds 

 oi oil were obtained from each charge. In the winter montl s 

 the yield was only about hall that amount. By the mechanics.] 

 means adopted the whole ot the spent leaves could be lifted 

 old under six minutes from the time the lid was removed. 

 Mr. E. Burgess.) • 



1'iaii No. in. A crude adaptation oi the .principle of distillation, 

 where the steam is produced outside the digester. The whole plant 

 consisted of three 400-gallon iron tanks ; one of these was used 

 as a boiler, another as the digester, while the third was the 

 condenser. The worm for condensing the steam was of copper 

 and the large still-head was also of copper. This plant was 

 working at Macedon, Victoria, distilling the "Peppermint" species. 

 (Mr. Saddington.) 



Plate No. 112. Another plant working at Macedon, Victoria, also 

 distilling the "Peppermint" species. The steam was produced 

 by a small boiler and the digesters were two 400-gallon tanks, 

 worked alternately, so that by preparing one tank while the other 

 was being distilled the process could be made continuous. The 

 water was supplied to the condenser by the aid of the windmill. 

 (Mr. Tovey. 



Plate No. 113 A plant at Huntley North, Victoria. The species 

 being worked was E. polybractea. The digester was constructed 

 of wood and was 8 feet by 5 feet 9 inches. The condenser was 

 made of copper. (Mr. Moyles.) 



Plate No. 114. A plant at Wyalong, New South Wales, employed 

 in distilling E. polybractea. The three digesters were of iron, sunk 

 in the ground, one holding about 2,500 pounds of leaf material, the 

 others a little smaller. A large Cornish boiler supplied the steam, 

 the working pressure being 30 to 35 pounds, and the time of 

 distillation two hours. The spent leaves were removed by 

 mechanical means. (Gillard Gordon, Ltd. 



Plate No. 115. A plant working E. polybractea, at Wyalong, New- 

 South Wales. There were two digesters sunk in the ground, the 

 larger holding about 3,000 pounds of leaf material. When in 

 full working order six digesters were distilled each dav, the time 

 for each being two hours. (Gillard Gordon, Ltd. 



Plate No. 116. A large plant at Whirrakee, near Bendigo, Victoria. 

 The two large digesters were built of wood, bound with iron, and 

 sunk in the ground. The lid was of wood also, with an outlet 

 in the centre made of copper. The digesters were 12 feet deep 

 with a diameter of 6 feet 6 inches, and held about 8,000 pounds of 

 leaf material. The best yield of oil was about 160 pounds for each 

 digester, although in the winter the yield was only about half 

 that amount. The condenser was laid in a concrete trench with 

 about 260 feet of piping, from 3 inches in diameter, diminishing 

 to ij inches. The boiler was a large Cornish one, 22 feet long, 

 and much of the spent leaf material was burnt in it. The crude 

 oil was refined by steam distillation in the ordinary way. The 

 chief species worked was E. polybractea. (The Hardinge Smith 

 Co-operation Ltd.) 



