This sentence is from a commentary on "Lord of the Files": Yet the tension in the group changes immediately into an excited rush when Ralph proposes building a signal fire on the top of the mountain which could be seen by any passing ship.

My question is: is it clear what the "which" refers to? I am concerned that, following the rule that the relative clause modifies the noun immediately preceding it, "which" refers to to the mountain rather than the fire. I tried adding a comma before "which". Does this help? Is the problem the position of "on the top of the mountain"?
You don't need a comma. I see your point, though. "Which" might be said to refer to the mountain. However, one might also say that from the point of view of getting the meaning across to the reader, it doesn't really matter here if "which" refers to the mountain, instead of the signal fire, since if the mountain can be seen by anyone, then the fire, being on top of the mountain, will also be seen. So it doesn't really matter here exactly what word "which" refers to, since the meaning gets across in any case. This is literature, and a skilful writer can bend the rules of grammar; indeed he should, or the text will read like a grammar textbook.
Anonymousis it clear what the "which" refers to?
It depends who you ask! To most native speakers with common sense, it's clear that 'which' refers to the fire. Emotion: smile

Language is notorious for underspecifying reality. We just have to learn to live with the fact that we can't leave our life experiences behind when we interpret language. Emotion: smile

A comma won't help. It certainly won't add any sort of mathematical precision, if that's what you're looking for.

CJ
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Thanks for the reply; I suppose the best strategy would be to move the adverb phrase, "on top of the mountain", wouldn't it?
Thanks for your reply. As a non-native (Polish) speaker, I'm quite obsessed with grammar rules such as those relating to commas and relative clauses. Emotion: smile
AnonymousI suppose the best strategy would be to move the adverb phrase, "on top of the mountain", wouldn't it?
You could do that, but I don't see any point in attempting to improve on the work of a well-known and respected author. Emotion: smile

CJ
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AnonymousAs a non-native (Polish) speaker, I'm quite obsessed with grammar rules such as those relating to commas and relative clauses. Emotion: smile
I had no idea the Polish people had such a soft spot in their hearts for commas! Emotion: smile

CJ