Really, really dull question about hyphenation and compound words

[VulpusinaWilfsuit]

Is there a general rule for hyphenation?

Because I cannot for the life of me work out why crossfire should be a compound word and cross-country should be hyphenated.

For example.

Et cetera.

Ad infinitem.

INteresting question. But I have no idea.

(apols for any typos: it was a long transcription and I should be doing other things!)

HYPHENS
We return here to our usual practice of disregarding everything not necessary for dealing with common mistakes. But general principles will be useful to start from.

1. Hyphens are regrettable necessities, and to be done without when they reasonably may.
2. There are degrees of intimacy between words, of which the first and loosest is expressed by their mere juxtaposition as separate words, the second being by their being hyphenated, and the third or closest by their being written continuously as one word. Thus hand workers, hand-workers, hand workers.
3. It is good English usage to place a noun or other non-adjectival part of speech before a noun, printing it as a separate word, and to regard it as serving the purpose of an adjective in virtue of its position; for instance, war expenditure; but there are sometimes special objections to its being done. Thus, words ending in -ing may be actual adjectives, or nouns, used in virtue of their position as adjectives; and a visible distinction is needed. A walking stick is a stick that walks, and the phrase might occur as a metaphorical description of a stiffly behaved person: a walking-stick or walkingstick is a stick for walking; the difference may sometimes be important, and consistency may be held to require that all compounds with gerunds should be hyphenated or made into single words.
4. Not only can a single word in ordinary circumstances be treated thus as an adjective, but the same is true of a phrase; the words of a phrase, however, must then be hyphenated, or ambiguity may result. Thus Covent Garden; Covent-Garden Market; Covent-Garden_market salesman.

That bit about the walking stick is rubbish, though!

In speech it totally depends on intonation, so a WALKing STICK is a stick which walks, and a WALKing stick is...well...you get it. It's really clear. The first example is so rare that in writing, it's not necessary to make that difference clear.

In writing some pairs of words have become compounded; some are always hyphenated; some are sometimes hyphenated; and some are never hyphenated. There is no hard and fast rule.

Generally if you use a two-word phrase as an adjective (as in part-time job) then you do use a hyphen, but even that's not a hard and fast rule.

senua that reads as though from an Edwardian grammar book! Where's it from?

Spot on with the Edwardian, Pruneurs. It's from The King's English by H. W. Fowler and F. G. Fowler, first pub 1906 although mine is a modern 1949 edition.

Did you note that they disagree with the rule that 'prepositions are something you should never end a sentence with'.

Aha, I thought Fowler's!

That rule was one of those bollocks Latin-is-the-root-of-linguistic-perfection jobbies, wasn't it?

I liked Churchill's take on it (apocryphal, no doubt).