Yes, correct - I don't want to bring the list too off-topic, but Unisys (UNIVAC + Burroughs) still maintains those two platforms (OS 2000 from the UNIVAC line and MCP from Burroughs), and they have a hobbyist program for both systems.

https://www.unisys.com/offerings/clearpath-forward/clearpath-forward-products/clearpath-os-2200-software/clearpath-os-2200-express

and

https://www.unisys.com/offerings/clearpath-forward/clearpath-forward-products/clearpath-mcp-software/clearpath-mcp-express

Unisys has also released older versions of MCP (1970s) as well with less restrictive licensing, and the community has built an emulator capable of running them on an emulated B5500 system - http://www.phkimpel.us/B5500/

The Burroughs MCP name supposedly inspired the MCP villain in TRON as well. 

I've never used Burroughs Algol nor Honeywell Algol, but I am aware you can use Honeywell Algol on Multics via gcos_tss (the GCOS Time Sharing Simulator).

-- Jeff

On Sep 3, 2018, at 7:41 PM, Dave Horsfall <dave@horsfall.org> wrote:

On Mon, 3 Sep 2018, Doug McIlroy wrote:

Was Algol 60 any kind of viable alternative at the time?

The operating system for the Burroughs B5000 had been written in Burroughs Algol. That punctured the widespread belief that OS's were so particular to the hardware that they had to be written in machine language. I don't recall how far Burroughs Algol went beyond Algol 60, nor why Multics did not want to follow that lead.  ("Viable" is a slippery concept when choosing among Turing-complete alternatives.)

Call me memory-challenged (which I am these days), but wasn't Burroughs' OS known as Master Control Program (MCP - Male Chauvinist Pig)?

-- Dave, who has fond memories of the B1500...