Technique of High Vaccum

Transcriped to Web format by Bruce Conover
SAS Technical Illustrations Department.

The following is a reprint of Chapter 3 of Procedures in Experimental Physics by John Strong. Chapter references within the text refer to that book. Due to the limitations of the markup language at the time that these pages were constructed, a few conventions have been modified as follows:

1. Footnote references, normally superscript numbers, now appear at the end of the text line and appear as bold numbers in bold square brackets such as [30].

2. Superscript notations are preceded by a carat symbol. For example:10^-3 should be read 10 to the minus 3.

3. Subscript notions have been eliminated entirely. Careful reading of the text and a comparison to the equation referenced should clear up any ambiguities.

4. All temperature measurements are in C and the degree notation has been eliminated.

Proceedures in Experimental Physics is a classic of experimental research and should be on the bookshelf of every amateur scientist. Originally published in the 1930's, it harbors an enormous wealth of practical information for any serious experimenter. The Society for Amateur Scientists strongly urges you to purchase this book. For more information, contact:

Lindsay Publications
P.O. Box 538
Bradley, IL 60915-0538
(815) 935-5353


This material was first published in the 1930's, back when folks were not so concerned about safety issues. Many of the techniques described here could be dangerous if proper safety precautions are not taken. For example, Mercury is a very dangerous substance to handle. While many of the techniques described in this material are quite valuable for the amateur experimenter, these are not for children! Make sure you take extreme precautions to keep yourself and your family safe.

Shawn Carlson
Executive Director
Society for Amateur Scientists


Part One

  • The laws of ideal gases.
  • Viscosity and heat conductivity
  • Pumping speeds
  • Conductance of vacuum pumping lines

Part Two

  • Roughing pumps
  • Vapor pressure of waxes
  • Getters
  • Static and kinetic vacuum systems

Part Three

  • Diffusion pumps
  • Mercury trap
  • Virtual leaks

Part Four

  • "Oil" traps
  • Electrodes
  • Valves
  • Mechanical motion
  • Leaks

Part Five

  • Vacuum gauges
  • The McLeod gauge
  • The ionization gauge
  • The Pirani gauge
  • The Langmuir gauge
  • The Knudsen gauge