Complete Extant Works of Hero of Alexandria, Vol. 3

There are some peculiarities in certain quaternions. And first, indeed, in the middle of the lower margin of leaf 10v, which is the last of the first quaternion, "α" is written; on the last leaves of the other bundles, no note of this kind is seen. Next, the eighth, which seems to be a quaternion, should be considered not so much a quaternion as a quinion, but one from which two leaves have been excised, of which traces still exist, albeit very meager ones (I shall call them a and b). The coherence of these membranes can therefore be represented in this way:

A diagram illustrating the physical structure of a manuscript gathering (quire). It shows a series of vertical lines representing folios, numbered 59, 60, 61, 62, 63, a, 64, 65, 66, and b. Horizontal lines connect pairs of folios to show they are part of the same sheet of parchment: 59 is connected to b, 60 to 66, 61 to 65, 62 to 64, and 63 is connected to a. The stubs 'a' and 'b' represent the excised leaves mentioned in the text.

The arrangement of the fourteenth quaternion is different; since four of its leaves have been cut out, which I shall call c, d, e, f, it bears this form: