On Jul 20, 2007, at 1:05 PM, John W. Kennedy wrote:

> No, the 7070, 7072, and 7074 were follow-ons to it.
>
> The IBM pre-360 commercial lines (-> incompatible; => compatible):
>
> The main scientific line
> 701->704=>709=>7090=>7094=>7094 II
>                 |
>                 .->7040=>7044
> (The 7040 line was a cheaper subset of the 7090 line. It did /not/  
> derive directly from the 704, as some have incorrectly concluded  
> from the number.)
>
> The famous STRETCH supercomputer. Not truly a failure, but IBM lost  
> money on it when they gave refunds because it wasn't as good as  
> promised. Still, a lot of STRETCH concepts, reworked, went into the  
> 360.
> 7030
>
> Budget scientific and real-time.
> 1620=>1710
> (The 1710 was a 1620 with command-and-control extras. There was  
> also a one-off 1720.)
>
> The main business line.
> 702->705=>705 II=>705 III=>7080
>
> Cheaper business machines (and upward extensions).
> 1401=>1460
>  | |
>  | .->1440
>  |
>  .->1410=>7010
> (The 1440 was an almost-compatible cheaper version of the 1401; the  
> only incompatibility was in the handling of punched cards and  
> printing. The 1410 was an incompatible upward extension of the  
> line; machine code was different, but carefully written assembler  
> code could be portable. Two more systems in the line were the 1240  
> and the 1420, which were essentially 1401s with magnetic-ink reader/ 
> sorters in the same chassis.)
>
> The first machine with a disk for business. Existing systems with  
> added disks were more successful.
> 350
>
> Budget general-purpose machines.
> 650->7070=>7072=>7074
>
> Almost a PC. Too little and too late to get much of a market.
> 610

That's pretty complete. I've never read a history of IBM -- I was  
going entirely from my memory of working with early IBM computers and  
the oral tradition transmitted me by the many IBM employees I have  
known over the years. BTW, you omitted the 1130, which I remember as  
small  scientific/engineering machine roughly contemporary with the  
1620. But we seem to have determined my memory isn't to be trusted.  
So where do you place the 1130?

Regards, Morton