This is the illustration from the  August 1966 issue of  Scientific American's  Amateur Science section.   This was perhaps the most inexpensive  and innovative vacuum demonstration  since the advent of the industrial era.   Things like a glass drinking straw,  Model T Ford spark coil and brass  ball point pen barrel are no longer  available.     This picture was taken off a micro  film viewer at the San Francisco  main public library.

      A year 2001 version of the linear peristaltic air pump.
 

This is a modern version of the linear peristaltic air pump.    Its design was inspired by both Nyle's prior art and my current knowledge of modern rotary oil-sealed   air pumps used for vacuum service.      Notice that the discharge tube is still running as seen in this picture.   This pump incorporates an exhaust check valve made from rubber bands over the exit end that prevents  the air from returning back to the evacuated pump and chamber when one stops rolling the hose.    Gone is the additional brayer guide. The hose is secured to the stick by the gaffer's tape.    Now the hose will not squirm out from under the brayers.   Additionally the stick with attached hose is secured to the table so the whole assembly will not wander  when rolled.   Additionally the long tube and the other dead volumes that connected the pump hose to the discharge  chamber have been eliminated;  minimizing the number of joins, using the maximum diameter of tube and the shortest connections  possible maximizes the effectiveness of this demonstration.   This is in accordance with good vacuum practice.   Because the discharge tube is small, in comparison to the swept pump volume, operating pressure is quickly reached with only  a few strokes of the hose with the brayers.

 

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