THE WORK OF THE FOREST DEPARTMENT IN INDIA. 35 



like crystals which are separated from the mother liquor by 

 throwing the magma into a sandpit. The tan liquor is absorbed 

 and the catechin remains as a soft pliable mass which is slowly 

 dried. This crude method of making katha is open to great 

 improvement, especially in separating katha from the liquor 

 in hand- worked filter presses and by drying the resulting mass 

 in a chamber heated to about 100 C. 



(/) ESSENTIAL OILS, OLEO-RESINS AND GUMS. 



(i) ESSENTIAL OILS. 



Sandalwood oil is distilled by the wet process from chips of 

 the heartwood of the sandal wood tree (Santalum album) the 

 root- wood being preferred. This valuable oil is largely used in 

 perfumery and in medicine. Before the war the wood was 

 largely exported to Europe for distillation, although this pro- 

 cess has always been carried out at various centres in India by 

 primitive methods. The question of improving the methods of 

 distillation is receiving attention in India, and it is hoped that 

 the time is not far distant when the whole output of sandal- 

 wood required for distillation purposes will be distilled in 

 India by modern methods and not exported for distillation 

 abroad. The Mysore Government is now working a distillery at 

 Bangalore with successful results. 



The eucalyptus oil industry has already assumed consider- 

 able proportions in the Nilgiris, but no expansion is possible 

 unless special plantations are formed for leaf supply. 



Rosha oil. One of the most important essential oils in this 

 country is East Indian geranium oil or palm-rosa-oil obtained 

 from the grass Cymbopogon Martini, Stapf. The distillation 

 of this oil was probably commenced in the 18th century, and it 

 was first brought to the notice of Europe in the early part of 

 last century. Recent investigations at the Forest Research 

 Institute have shown that improvements in distillation can be 

 effected by employing a modern type of steam still. The main 

 conclusions arrived at are that it is more economical to distil 

 the grass with steam and that 20 per cent, more oil can be 

 obtained in this way. By redistilling the crude oil, a water- 



