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From: yarvin-norman@CS.Yale.EDU (Norman Yarvin)
Newsgroups: comp.arch
Subject: Re: Mercury delay lines
Message-ID: <25376@cs.yale.edu>
Date: 12 Jun 90 02:38:16 GMT
References: <EaQvAbO00Ug7A7a68t@andrew.cmu.edu> <10814@medusa.cs.purdue.edu>
Sender: news@cs.yale.edu
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In article <EaQvAbO00Ug7A7a68t@andrew.cmu.edu> aw1r+@andrew.cmu.edu (Alfred Benjamin Woodard) writes:
>I've been following this thread for quite a long time and being a
>computer history / trivia buff I am curious what Mercury Delay lines
>were. It seems really weird reading about all the computers that used
>them and not knowing what they were,

A tube of mercury, with a speaker at one end and a microphone at the other.
(actually, transducers at both ends.)  Sound takes time to travel, so there
is a delay between driving the speaker and getting a response.  I presume
mercury was chosen for its acoustic properties (high density for high sound
energy, liquid for immunity from shear waves).
--
Norman Yarvin				yarvin-norman@cs.yale.edu