'He won’t/never set the Thames on fire'

[Tamara]

Hi

From my old A Picture Book of Idioms in Five Languages (1993):

He/she doesn’t snatch stars from the sky. – Russian version (in English translation)
He didn’t invent powder. – French, Spanish, Russian,..
He is not a great torch-bearer. – German

He won’t set the Thames on fire. - English

This English saying is obviously rises curiosity – why do you say it so – referring to the impossible event?

(Or maybe, 'set on fire' is used here in some indirect sense – in particularly, I saw old English pictures with great national celebrations (or grief for actually great persons, like Lord Nelson…) and the Thames on them can actually be viewed as being 'on fire'.

?
_________________
It’s impossible to learn swimming without entering the water…

[Conchita]

The phrase might originate from a Latin saying.

I think the Phrase Finder gives a reasonable (and interesting!) explanation:

http://www.phrases.org.uk/bulletin_board/6/messages/596.html

Brewer’s dictionary also has an amusing entry on this:

[Jamie (K)]

We don't have the Thames here in America, and we don't think about it much. We say instead, He won't set the world on fire. You can replace the world with other things, such as the engineering profession, his field, etc.

By the way, it's not impossible for a river to catch fire. In the 1970s, both the Cuyahoga River in Ohio, and the Rouge River in Michigan, became so polluted that they actually caught fire. Now they have been cleaned up, and people can actually fish in them.

[Tamara]

So this means that that poor 'someone' hasn’t got enough 'internal fire' (talent, curiosity, etc.) to become actually great in doing something.

Now I see. In my language we say God’s spark for that.

Thank you!

[Jamie (K)]

[Yankee]

[Tamara]