THE scarcity of rubber is being felt more and more in Sweden. While through a rapid perfection and large-scale adoption of producer-gas the motor fuel problem has been relatively satisfactorily solved, it is now the shortage of rubber and lubricants that is the great cause for anxiety and which has made necessary the imposition of further restrictions on motor traffic. To try to improve the situation, experiments with the production of synthetic rubber have been going on for some time at various institutions. Promising results have been reported from the Physico-Chemical Institute at Uppsala, where experimental production has been carried on under the guidance of Prof. The Svedberg, as well as by the Swedish cellulose concern, Mo and Domsjo, which has evolved a product that is stated to be able to replace rubber for many purposes and which will be produced on a commercial scale in the near future. A young Swedish scientific worker, Dr. Gosta Ehrensvard, of the Wenner-Gren Institute in Stockholm, has succeeded in developing a kind of artificial rubber which seems to possess several good qualities. Production on a small scale has been going on for some time at one of the rubber factories of the Swedish Co-operative Wholesale Society, which is supporting his researches and will probably exploit the new product. It belongs to the so-called 'thioplast' products, the weak point of which has hitherto been that they could not be vulcanized at a high temperature. This can, however, be done with the Ehrensvard rubber. The unpleasant odour that formerly characterized such products has also been eliminated. Nothing has so far been said about the composition of the new product or of what raw materials it is being made, except that it is based on domestic raw materials and that the Swedish forests, in this as in so many other cases, will play an important part.