270 
Indian Forest Records. 
t?OL. I. 
appear to have been jealously kept back by the ‘ celestial ’ manufac- 
turer. We are not told, for instance, if any oil is obtained as a by- 
product from the plant. Further, information is not available on the 
important points, whether the plant is subjected to some preliminary 
mechanical, chemical, or other treatment to obtain from it the maximum 
yield of the camphor ; whether only Blumea halsamifera alone, 
or together with other camphor-yielding species, is utilized for 
camphor distillation ; whether any substance is added to the still to 
facilitate the subhmation of camphor. Apart from the scientific 
interest attaching to them, the solution of these questions has a direct 
practical bearing on the expansion of the ngai camphor industry. It 
has not been possible to undertake a systematic investigation to 
elucidate these obscure points ; but it may be noted here that in 
the course of a series of experiments made on the distillation of the 
Blumea halsamifera of Burma answers were incidentally obtained to 
some of these questions. These answers which appear to me to be 
more or less conclusive, will be dealt with later on. 
The question of camphor distillation in Burma being of great econo- 
mic importance, it has of late been occupying the attention of the Forest 
Department. Since the subject required to be investigated both in an 
economic and a chemical direction, it was submitted by the Chief 
Conservator of Forests, Burma, who took up the matter, to the Imperial 
Forest Research Institute. The first question was to design an ex- 
perimental still of sufficient capacity to see if camphor could be manu- 
factured on a commercial scale from the Blumea halsamifera D.C. of 
Burma. The next point that required a chemical investiga- 
tion was to determine the total percentage of essential oil in the 
fresh green plant and to compare it with the percentage obtained from 
the plant in its dry state. These analytical determinations were made 
with the plants growing in the Tarmgoo and the Katha Divisions during 
my recent tour in Burma, undertaken with the permission of the In- 
spector General of Forests, with the object of investigating some important 
points connected with camphor distillation. Before the results of these 
analytical experiments and of the experimental distillation of the plant 
with the still referred to above are given, it is considered desirable, for a 
better understanding and appreciation of the results, to describe briefly 
the plant and the chemistry of ngai camphor (showing its relation with 
the common or Laurus camphor), together with the methods of plant 
analysis for moisture and volatile oil determinations. 
