The beginnings of a successful story

The exciting invention of the molecular Pump by Wolfgang Gaede was followed by his new 'device of Producing High Vacua' in 1913. it was announced in the second edition 1913 of e. Leybold's cataloge. three years later Langmuir in the usa presented a similar pump called 'condensationpump', but with clearly better pumping speed. another design of a pump with two stages was invented by Prof. Volmer in Berlin. other european companies announced similar pumps. Because Gaede claimed the prinziple of evacuating gas by diffusion, he and Leybold succeeded in making all of them to ask for licences. respective to Langmuir they exchanged licence to each other. By the time this 'diffusion pump' was produced from metal instead of glas, and used special mineral oil, not mercury. in the middle of the 20. century it became a most important tool for creating high vacuum, available with a few liters per second to some thousend liters of pumping speed.