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Vacuum science and technology has a unique

and interesting history.

As early as the 5


century BC, the Greek

Philosopher Democrite predicted that

matter was made of atoms and vacuum.

However soon after, believing that “nature

abhors a vacuum”, Aristote and some

other ancient scholars denied the concept

of a vacuum and the possibility of a void.

The belief that vacuum was impossible

existed well into the 17


century although

early in that century sceptics were

beginning to question the ancient “fear of

vacuum” concept. This was motivated by

the failure of siphons and the inability of

pumps to “suck” water above heights of

about 10 meters. By mid-century, piston

vacuum pumps were in use and vacuum

science was on its way. It is not surprising

that these early pumps resembled

the water pumps that preceded them

(not unlike the way in which the first

automobiles resembled horse-drawn


The next two hundred years were spent in

improving these pumps and in measuring

and characterising vacuum. Progress was

very slow by today’s standards. However,

at that time there was not an urgent need

for vacuum although a few scientists began

to use vacuum as a tool for their research.

The study of electrical discharges at low

pressures was an early example of a study

that continued all through the evolution of

vacuum science and technology.

By the latter part of the 19



vacuum technology had advanced to

the point where pressures of 0.1 Pa

or better were achieved, thus making

possible the discovery of the electron,

thermionic emission and x-rays, and

the invention of the incandescent

lamp. The commercial implications

of these developments created an

unprecedented need for the produc-

tion of vacuum on an industrial scale.

Consequently vacuum technology

advanced at an almost explosive rate

by the turn of the 20


century and

was followed by many innovations in

the production and measurement of

vacuum for research and industrial



years of the Union




vacuum societies