Olin,

On Fri, 2 Sep 2005 14:50:37 -0400, Olin Lathrop wrote:

>...<
> And back an even longer time ago, analog delay lines were used to store
> digital information.  Some early computers used essentially long
> transmission lines to store bits.  

Known as "delay lines"...

> Some even stored bits as accoustic signals on long rods. 

... and a common medium was a tube containing mercury, with pulses of "sound" injected at one end and read out 
at the other.  Another technique was charges stored on a CRT screen, and most of these early storage methods 
were volatile, and had to be refreshed regularly or the stored data decayed.  The advent of magnetic core 
storage was something of a breakthrough because it was static. I once saw an ICL mainframe (which was old even 
then in the mid 1970s) that could be powered-up and carry on where it left off, without any sort of boot 
process, because its main memory was core, and still held the operating system, programs and data from when it 
was last used.  Semiconductor memory isn't an unconditional improvement!  :-)

Whatever happened to "bubble memory", which in the 80's was going to take over from magnetic media?

> This was back when a Kbyte was a lot of memory (and
> before bloatware so that you could actually do meaningful things in a Kbyte).

Indeed - in the early 1970s I was an operator on an IBM mainframe with 96k of memory on which we ran the 
operating system, spooling system, and three application programs at once, and it didn't even use Virtual 
Storage - that 96k held it all at once!  We ran three companies' entire businesses on that, along with two 
programming offices' development.  Mind you, compile/test cycles were at most two a day, so desk-checking your 
coding was a Good Thing if you didn't want to waste a half or a whole day due to one little typing error.

Then there's disk storage - we had five wardrobe-sized cabinets that held one fifth of the amount of data that 
I can now hide under my watch!

Tell that to kids today, and they won't believe you...  :-)

(/ "When I were a lad" mode)

Cheers,


Howard Winter
St.Albans, England


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