At the very end of his preface to the OCT edition of Pliny the Younger’s letters, R. A. B. Mynors writes:
In textu distinguendo uereor ne qui hodiernum desideret usum distinctionum haereat lector, cum illud semper in animo habuerim ut numeris Plinianis geram morem; auribus enim, non oculis modo uerum etiam auribus legendus est noster.
I don’t quite understand, and I think the problem is the meaning of distinctio and numerus in this context. My translation:
In distinguishing(?) the text I fear that the reader who prefers the use of modern distinctions(?) will be at a loss, since I have always taken care to honour the Plinian numbers(?); for our author is to be read not only with the eyes but also with the ears.
This is obviously nonsense, so what does it mean?
I think “distinguere” is to be understood as “divide” (into sentences, clauses and/or paragraphs). In the plural “numeri” can mean something like “harmony” or “rhythm”.
So the editor is saying that he divided the text not according to modern (English?) customs (usus hodiernus) but with regard to the rhythm and flow of Pliny’s writing because he wanted to create a text that can be read aloud easily, as was common in antiquity.
Remember that the punctuation and division into paragraphs found in modern editions are not ancient, but established by modern editors.
That all sounds very reasonable! Thank you for clearing it up.
Just to clarify Laurentius’ explanaton, distinguendo and distinctionum refer to punctuation; numeris Plinianis refers to Pliny’s prose rhythms.