One of the 1972 editions of the long-running science fiction anthology series. I was always very fond of this series, but I found it hard to connect with some of the stories in #20. In fact, half way through I was thinking that there was no point in keeping it once I'd read it, as even the ones I liked didn't make me feel inclined to re-read them.

Conversational Mode by Grahame Leman -- decidedly grim short which consists of a transcript of a conversation between an involuntarily committed patient in a mental hospital and a psychiatric program running on a computer. The story is really about the potential abuse of psychiatry rather than the mechanics of such a program, but even so I was rather distracted by early 70s mainframe computer output conventions in software that is clearly at least as sophisticated as any of the AIs running in Turing Test competitions in 2010. Not one I feel inclined to re-read.

Which Way Do I Go For Jericho? by Colin Kapp -- It's the middle of a war, and a scientist volunteers for a military intelligence operation in which he will be left behind as an apparent civilian refugee after a military pullout. The aim is to give him a chance to look at a new sonic laser weapon being used by the enemy. The catch is that he will have to be a very convincing refugee, to the point of making him so starved and ill before the pullout that he will barely be able to function. It's the sort of science/engineering problem in harsh conditions story that Kapp was so good at. I liked it but am not inclined to re-read it.

Microcosm by Robert P Holdstock -- an astronaut visits an alien planet and gets caught in two time streams. I didn't entirely understand it and didn't like it. A complete waste of time as far as I was concerned.

Cain(n) By HA Hargreaves -- long story about the rehabilitation of a young teen who has been caught for some crime which has been wiped from his memory as part of the rehabilitation process. It's clear from what he does remember that he has been homeless and living on the streets for years, and has no clear idea of what happened to his family. Beautifully and movingly written to show how he is slowly resocialised and comes to recognise that what he initially perceives as punishment genuinely is an attempt to rehabilitate him to the point where he is fit to serve his time.

Canary by Dan Morgan -- The canary in question is a human being used the same way that canaries were used in mines -- he's a psychic who's sensitive enough to the possibility of his own death that he can be used as an early warning of the outbreak of nuclear war. There's some nice discussion of the problems faced by the sane members of government on both sides of a cold war in trying to stop their hotheads from stirring up trouble.

Oh, Valinda! by Michael G Coney -- on an alien planet, icebergs are harvested for fresh water. Since the locals sold the rights to the icecaps to humans long ago before they realised there might be any value to them, it's the humans who transport the icebergs to the seaboard cities where they're needed. But the unusual mode of transport requires the help of a hired local -- some of the icebergs are inhabited by giant worms who ingest seawater and filter it for food before expelling it. Persuade the worm to point in the right direction and the water jet can propel the berg. But it's a complicated business finding a worm and keeping it going... ( )