In Mr. Beatty's original acquisition there were ten leaves, in conjoint pairs, containing portions of Romans on the first halves, and portions of Philippians, Colossians, and 1 Thessalonians on the second - evidently, therefore, part of a single-quire codex of the Pauline Epistles - and calculations of space made it probable that Hebrews had been included in the missing intermediate portion.
This calculation was confirmed when, shortly after the ten leaves had been published by the present writer, it was announced that the University of Michigan had acquired thirty more leaves of the same codex, in excellent condition, which showed that Hebrews was indeed included, and was placed immediately after Romans.
Scarcely had these been published by Professor H. A. Sanders, of Michigan, together with the ten Beatty leaves, when they were capped by the acquisition by Mr. Beatty of forty-six leaves more. 
The entire manuscript therefore consists, in its present state, of eighty-six nearly perfect leaves out of a total of 104, of which the last five were probably blank; at least they are not needed for the completion of Thessalonians, and would not be enough for the Pastorals, which seem to have been omitted.

Description & picture from 'Our Bible & the Ancient Manuscripts' by Sir Frederick Kenyon (1895 - 4th Ed. 1939) Pg 126 & Plate VIII. (Page fragment illustrated: 21.25 x 15cm.)