402 
NATURE 
[JUNE 20, 1912 
PRODUCTION OF SYNTHETIC RUBBER. 
@r Monday, June 17, Prof. W. H. Perkin 
~ read a paper of very great interest before 
the Society of Chemical Industry. It has long been 
the desire of chemists to synthesise rubber by a 
method which would permit of cheap production on 
a large scale, and very many attempts have been 
made to do this. When the extraordinary boom 
in rubber set in a year or two ago, everyone was 
looking about for new sources of the material, and 
artificial rubber after artificial rubber was brought 
out. The term artificial was, indeed, the right 
one to apply, because the substances were none of 
them synthetic—in fact, as a rule, contained 
greater or less quantities ‘of natural rubber, mixed 
with other substances. On Monday night, how- 
ever, Prof. Perkin was able to announce that 
rubber has actually been synthesised, and that this 
synthetic rubber can be placed on the market at 
a price to compete with plantation rubber. 
From long and arduous research work it was 
known that “if isoprene, divinyl, and similar com- 
pounds could be obtained cheaply, it would be pos- 
sible to polymerise them and convert them into 
rubber. But here was a very difficult problem. 
Turpentine could be used, but the price of tur- 
pentine was too high. The aim was to endeavour 
to find a substance from which rubber might be 
manufactured at about 1s. per Ib. For this pur- 
pose the only substances which it seemed possible 
to use were wood, starch, sugar, petroleum, or 
coal. The product finally chosen was_ starch, 
which can so readily be obtained in the form of 
cereals, maize, or tubers at a price which works 
out at less than one penny per pound. By a pro- 
cess of fermentation, fusel oil can be obtained from 
starch and starchy material. It was, however, 
necessary to devise a cheap fermentation process, 
and Prof. Fernbach, of the Pasteur Institute, was, 
produce a fermentation process for the production 
of fusel oil from any starchy material. The pro- 
cess is now so satisfactory that the higher alcohols 
can be obtained at a cost of not more than 30l. 
per ton. 
Having produced isoprene cheaply, the next con- 
sideration was how to polymerise it and convert 
it into rubber satisfactorily. The discovery of 
the cheap method for preparing isoprene was first 
suggested by Dr. Matthews. In 1909 Mr. E. 
Halford Strange, of Messrs. Strange and Graham, 
technical research chemists, directed his organisa- 
tion of chemists, headed by Dr. Matthews, to the 
problem of the synthetic production of rubber. 
Dr. F. E. Matthews suggested one method for 
preparing isoprene in which acetone was one of 
the raw materials, and later on one in which fusel 
oil was the starting product. 
Prof. Perkin was then asked to cooperate, and 
later on Sir William Ramsay joined the group as 
consultant. Afterwards Prof. Fernbach, of the 
Pasteur Institute, also cooperated. In July, 1910, 
Dr. Matthews left some metallic sodium in con- 
tact with isoprene, and on returning from his 
holidays in September found that the isoprene had 
NO. 2225, vor. 89] 
turned into a solid mass of rubber. On further 
investigation it was found that sodium is a general 
polymerising agent for this class of material. 
Strangely enough, the first announcement of this 
discovery was made by Prof. Carl Harries, of 
Germany, who had made the same discovery in- 
dependently, about three months later. Owing to 
the English patent not having been published, 
Harries was unaware that his discovery had been 
anticipated. It is interesting to note that the 
competition in other parts of the process has been 
almost equally keen. The-two parties reached the 
goal by different paths, but the British chemists 
were there first. 
One very great point about this most recent 
discovery is that synthetic rubber does not contain 
impurities, and the process of manufacture can 
be carried out either in the cold or at moderate 
temperatures. 
In connection with the manufacture of rubber 
another discovery of great, almost of vital, im- 
portance has also been made—the production of 
acetone cheaply. For the manufacture of am- 
munition, acetone is of the utmost importance. 
Every Government in Europe requires acetone, 
and the supply is limited. From the point of 
view of the national defence, the discovery of a 
cheap précess for obtaining practically unlimited 
supplies of acetone cannot be overestimated. 
THE TRANSMISSION OF SLEEPING 
SICKNESS. 
See Ns have been published recently in 
The Times and other daily papers, on the 
authority of Reuter’s Agency, that, according to 
reports received from the Commission on Sleeping 
Sickness working in Rhodesia, it has now been 
proved beyond a doubt that the tsetse-fly known 
| as Glossina morsitans can act as a carrier of the 
after eighteen months of laborious work, able to | 
“bacillus” of sickness as well as 
G. palpalis. 
These statements refer, apparently, to the work 
of Kinghorn and Yorke, which was published in 
the Annals of Tropical Medicine and Parasitology, 
March, 1912, and of which a full report appears 
in the last number (37) of the Bulletin of the 
Sleeping Sickness Bureau. Kinghorn and Yorke 
experimented with the trypanosome which is the 
pathogenic agent of sleeping sickness in northern 
Rhodesia, and which has been given the name 
Trypanosoma rhodesiense by Stephens and 
Fantham, since it shows certain differences from 
the typical T. gambiense of sleeping sickness in 
Uganda. They found, by experiments both with 
laboratory-bred flies and with flies caught wild 
and naturally infected, that G. morsitans can 
transmit the trypanosome to monkeys and other 
mammals. 
Approximately 5 per cent. of the flies become 
infective, acquiring this power after a non- 
infective period of about fourteen days, during 
which the parasite is doubtless passing through a 
developmental cycle in the fly; the fly then retains 
the power of transmitting the disease during its 
life, and is infective at each meal. The authors 
sleeping 
oes 
