question about latin usage of colon

[Franmorar]

Franmorarius interretialibus comitibus sautem dicit plurimam.
Please, could anybody explain the usage of colon (:) in Latin? I have read a certain amount of Latin texts in their "original" versions (in fact, as you know, critic editions, not gradually arranged to freshmen), but, untill now, I have not been successful to discover or deduce any concrete or sure rule of usage. I am already aware that punctuation marks are not part of original ancient works, and they were progressively added and established during late Antiquity, Middle Ages and Renaissance.
So, could anybody help?
Thank you in advance.
Valete.

[Alatius]

I don't think that there is a specific usage of this sign in Latin, compared to other languages. Generally, I believe, it is used between closely connected sentences, much in the same way as a semicolon, with the possible difference that the colon is used when the later sentence clarifies the first. Do you have an example of a colon that you think is used in a peculiar way?

[thesaurus]

I don't know about Latin specifically, but the use and meaning of punctuation like the colon have been changing over the years. There haven't always been clear rules, nor are there universal and fixed rules till this day. If you look at English from the last few centuries, you'll see differing usages through time. By modern standards, it can be really strange at times, varying within a period and even within the works of a single authors. It's only recently that we've attempted to truly standardize punctuation to meet stylistic guidelines.

I imagine all of this applies to Latin texts as well as vernacular ones, considering that modern editors are creating these "critical editions". Editors necessarily have to make choices about how they are going to present the text, and if they are editing something that is originally unpunctuated, they will undoubtedly follow their own judgments, education, and the prevailing style of the time.

[adrianus]

"A colon, on the other hand, is the expression of a thought which is rhythmically complete, but is meaningless if detached from the whole body of the sentence." (http://penelope.uchicago.edu/Thayer/E/Roman/Texts/Quintilian/Institutio_Oratoria/9D*.html#1)

I understand that the symbol ":" is 14th century, but the basic idea is obviously very early.
Saeculi quarti decimi est signum ":" videlicet, ut legi, at nimiò antiquior est cognitio.

Colon = membrum corporis = sententiae membrum,
which isn't far from our modern meaning: behold this bit or bits of a list.
quod non longe errat ab significatione modernâ: ecce partem vel partes tabulae.

[cb]

hi, here are explanations (in latin) of the colon-mark by aldus manutius the younger (epitome orthographiae, 1575) and by voss (latina grammatica, 1669): i have taken photos and marked the parts relating to the colon-mark in red boxes:

aldine 1575: http://mhninaeide2.webs.com/Aldine1575OnColonMark.pdf
voss 1669: http://mhninaeide2.webs.com/Voss1669OnColonMark.pdf

another book on latin orthography (cellarii orthographia latina) follows the aldine description above. it's online, here is the link (see pgs 73 and ff.):

http://books.google.fr/books?id=6xwPAAAAIAAJ&pg=PA73

cheers, chad