5 ° 
Getali Jelutong or Pontianac, is usually stated tQ be obtained from 
D v er a costulata, a large tree which is fairly common throughout the 
Malayan region, but it is probable that the material as met w.th in 
commerce is a mixture of guttas derived from different sources. It 
has been stated, in fact, that it is the custom of the natives to mix 
the latex of the Jelutong tree with that derived from different species 
of U 'illoughbeia, which yield inferior rubbers. The value of Ponti- 
anac in the London market is about $19 to $20 per ton, but as al- 
ready stated, the chief demand for the material is in the United 
States, which in 1901 imported 9,371.037 lbs., valued at 1248,838. 
Of this total, 8,708,107 lbs. are returned as coming from the 
British East Indies, probably through Singapore, whilst the re- 
mainder, 662,980 lbs., was imported from the United Kingdom. 
After undergoing certain treatment, the Pontianac is chiefly em- 
ployed in the United States as an ingredient in the mixtures used 
for the manufacture of rubber goods of low quality, and its utilisa- 
tion for such purposes appears to be extending. 
The sample of Getali jelutong from Sarawak was almost identical 
in appearance, composition and properties with commercial samples 
of Pontianac. being remarkably free from admixture with vegetable 
or mineral impurities, and it would, no doubt, he suitable for any 
purpose for which the latter is employed. At present, however, the 
material is of relatively small commercial value. 
Two specimens of the mineral substance used in the preparation 
of Getah Jelutong were supplied : one of the mineral as imported, 
the other of the material prepared for use by heating. i he mineral 
proved to be a specimen of the fibrous variety of gypsum, known as 
l satin spar” {hydrated calcium sulphate) ; it was white, translucent, 
crystalline and massive. 
The specimen which had been heated was white and opaque; it 
was non-crystalline, but retained the fibrous form of the mineral, 
and readily crumbled to powder in ihe fingers. It absorbed water, 
but did not set like plaster of Paris. It contained only 2.48 per 
cent, of water, so that in course of preparation the gypsum has 
probably been heated to a high temperature, with the result that the 
product does not set when mixed with water. 
If as is indicated, the addition of this substance is essential in 
the preparation of the gutta, it is probably due to the fact that the 
iatex*is coagulated by a solution of calcium sulphate, as is known 
o be the case with several other rubber latices. 
Supplement to the Board of Trade Journal. July 9, 1903 , p. 63. 
Recent Publications on Rubber and its 
Cultivation. 
In the E’tudes Coloniales for October 1903, Mr. OCTAVE J. A. 
Coi let publishes an interesting and well illustrated paper on 
“ L Ilevea Asiabque,” based on bis experiences in the Malay 
Peninsula, and well illustrated. He points out that at the end of 
