ISEN-ASTC-L is a service of the Association of Science-Technology Centers
Incorporated, a worldwide network of science museums and related institutions.
*****************************************************************************

Actually Martin,,, the first example of an exhibit like
this that I know of was in the US Science Pavilion
at the Seattle Worlds Fair in 1962 (now the Pacific
Science Center)

This one had the bell as well as an altimeter and
a radiometer in the bell jar.  It showed that you could
no longer hear the bell since there was no air for the
sound to travel through, but the radiometer kept turning
because light travels through a vacuum.

David Taylor
AHHA Museum Services
  "Now I Understand"
    (206) 363-8126
   e-mail:   [log in to unmask]
http://www.AHHA-MuseumServices.com
========================================

> From: martin weiss <[log in to unmask]>
> Subject: Re: What To Do With A Big Vaccum Pump? An Exhibit?

> There is an exhibit I've seen several places,
> Science Museum of Minnesota most recently,
> (originated where?) that demonstrates a feather
> and a marble falling at the same rate in a vacuum
> and at different rates in air. Though I knew the
> principle seeing it was astounding.
>
> My recommendation.
>
> Cheers,
>
> Martin
>
>>
>> Wayne,
>>
>> I've seen an exhibit that had a solenoid/rod
>> ringing a bell in a bell jar. The solenoid was
>> activated by visitors with a push button. The
>> bell jar was vacated by the vacuum pump and the
>> sound of the bell slowly died away.
>>
>> Dick Falkard
>>
>> -----Original Message-----
>> From: [log in to unmask] [mailto:[log in to unmask]]
>> Subject: Re: What To Do With A Big Vaccum Pump? An Exhibit?
**********************************************************
>>
>> Wayne,
>>
>> Edward's is a major manufacturer of vacuum
>> pumps. They make/ made several different kinds.
>> If you do an online search you can probably come
>> up with not only all the spec.'s but also
>> exploded views of all the little parts the thing
>> is made up with - as well as the parts you will
>> need to rebuild the thing if it has been sitting
>> around for a while.
>>
>> The motor size you quote indicates a huge vacuum
>> pump. Currently they offer a E2M40 which has a
>> capacity of 30 cfm - that's about 10 times
>> greater than any pump I've ever used in an
>> exhibit. This one only uses a 2 HP motor so I'm
>> it's unlikely that this is the same one you've
>> got.
>>
>> The chief advantage to a large pump in our case
>> is speed. It can evacuate a chamber relatively
>> quickly. This way visitors don't have to wait a
>> long time (30 sec to a minute) for a reasonable
>> vacuum to be reached.
>>
>> Usually vacuum pumps run continuously (though I
>> don't know about the type you've got) - you turn
>> a valve to connect the pump to the systems
>> rather than turn the pump on and off. It's
>> unlikely that you'd want to run a 25 hp motor
>> all day (assuming you even have the service
>> available to run it.)
>>
>> As far a what to do with it. You're guess is as
>> good as mine, but probably not as good as some
>> others out there.
>>
>> Joe R
>> TheExhibitGuys.com

>> Wayne Watson wrote:
>>>
>>>  Someone gave the museum what we call a large vacuum pump. It has a 25
>>>  hp motor, is about 18" on a side, and says in large bold letters 40
>>>  with the words Two Stages below it. The mfger seems to be Edwards. It
>>>  looks like it would evacuate all the air from a large room. I may have
>>>  been used in the semiconductor industry. Any suggestions on how we
>>>  might use it for an exhibit?
>>>
>>>  --
>>>       Wayne T. Watson (121.015 Deg. W, 39.262 Deg. N, 2,701 feet,

***********************************************************************
More information about the Informal Science Education Network and the
Association of Science-Technology Centers may be found at http://www.astc.org.
To remove your e-mail address from the ISEN-ASTC-L list, send the
message  SIGNOFF ISEN-ASTC-L in the BODY of a message to
[log in to unmask]