Under the siglum sa 297L, Schmitz and Mink’s list of the Sahidic New Testament manuscripts mentions a number of fragments from a lectionary which belonged the Monastery of Shenoute, i.e. the White Monastery. Schüssler’s Biblia Coptica designates the same manuscript as 818L. Although the script has variously been dated to the 9th or 10th century, I would rather opt, on paleographical grounds, for an 8th century dating.
Here are the known fragments of this codex:
London, British Library, Or. 3578B, f. 21
Paris, Bibliothèque nationale de France, Copte 129(21), f. 5-8
Paris, Bibliothèque nationale de France, Copte 132(3), f. 180
Paris, Bibliothèque nationale de France, Copte 133(1), 51, 51a-b
Vienna, Österreichische Nationalbibliothek, K 9648
Vienna, Österreichische Nationalbibliothek, K 9673b
And a few random photos of some of the fragments (sorry for their bad quality):
Although scholars have sometimes quoted this lectionary, I think no one has remarked until now that it represents something of an oddity: as far as I am aware, it is the only Sahidic manuscript which has three columns of text on a page.
There are Greek manuscripts written in three columns (Vaticanus) or even four (Sinaiticus). I know that this is typical also for Syriac and some Ethiopic manuscripts. However, sa 297L stands out as the only example of a Coptic manuscript with more than two columns per page.
I am not sure why the scribe decided to organize the page in this way. Does it have something to do with the exemplar he used? In any case, this is certainly something strange enough to be worth noting.