Lecture Demonstration

Infobox short story
name = Lecture Demonstration
author = Hal Clement
country = United States
language = English
series =
genre = Science fiction
published_in =
publication_type = anthology
publisher =
media_type = Print (Hardcover)
pub_date = 1973

'Lecture Demonstration" is a short story by Hal Clement. It was first published in in 1973.

Plot introduction

The story laid on the planet Mesklin as used in the author's novel Mission of Gravity, but set in an earlier period when the College established by the Terrestials is still being set up and the teachers as well as the students are still learning.

Plot summary

Dr LaVerne, a teacher with the College, takes a party of Mesklinite students on a geological expedition. Whilst examining a layer of rock, it collapses. Teacher and students fall into a cavern. They are unable to climb out; the limiting factor is time as the teacher is enclosed in a suit with a finite oxygen supply.

The students and teacher discuss various possibilities until the realise that they can raise the melting point of the surrounding ammonia 'snow' to the point where it soldifies. They climb out to safety.