linkages break
and so permit the two chains of 4 C's to unite to form one ring of
eight. If you have ever played ring-around-a-rosy you will get the idea.
In Chapter IV I explained that the anilin dyes are built up upon the
benzene ring of six carbon atoms. The rubber ring consists of eight at
least and probably more. Any substance containing that peculiar carbon
chain with two double links C=C-C=C can double up--polymerize, the
chemist calls it--into a rubber-like substance. So we may have many
kinds of rubber, some of which may prove to be more useful than that
which happens to be found in nature.

With the structural formula of Harries as a clue chemists all over the
world plunged into the problem with renewed hope. The famous Bayer dye
works at Elberfeld took it up and there in August, 1909, Dr. Fritz
Hofmann worked out a process for the converting of pure isoprene into
rubber by heat. Then in 1910 Harries happened upon the same sodium
reaction as Matthews, but when he came to get it patented he found that
the Englishman had beaten him to the patent office by a few weeks.

This Anglo-German rivalry came to a dramatic climax in 1912 at the great
hall of the College of the City of New York when Dr. Carl Duisberg, of
the Elberfeld factory, delivered an address on the latest achievements
of the chemical industry before the Eighth--and the last for a long
time--International Congress of Applied Chemistry. Duisberg insisted
upon talking in German, although more of his auditors would have
understood him in English. He laid full emphasis upon German
achievements and cast doubt upon the claim of "the Englishman Tilden" to
have prepared artificial rubber in the eighties. Perkin, of Manchester,
confronted him with his new process for making rubber from potatoes, but
Duisberg countered by proudly displaying two automobile tires made of
synthetic rubber with which he had made a thousand-mile run.

The intense antagonism between the British and German chemists at this
congress was felt by all present, but we did not foresee that in two
years from that date they would be engaged in manufacturing poison gas
to fire at one another. It was, however, realized that more was at stake
than personal reputation and national prestige. Under pressure of the
new demand for automobiles the price of rubber jumped from $1.25 to $3 a
pound in 1910, and millions had been invested in plantations. If
Professor Perkin was right when he told the con