From Alan Bowman and David Thomas, Vindolanda:
the Latin writing tablets London: Society for the Promotion
of Roman Studies, 1983, pp. 67-68
In Section D we have been concerned exclusively with the normal
type of writing in use in the tablets. The only exceptions to this
writing are (a) Tablet No. 11 (163),
which is written in a capital script and (b) the addresses which
are written on the outside of several of the letters in what we
have designated 'address script'.
It is in no way surprising that an example of capital script should occur in the tablets, since the use of capitals for military documents, or at any rate for headings within such documents, is well attested in Latin papyri100. It is, indeed, rather surprising that there is only one example of the use of capitals in the Vindolanda material. The script of No. 11 (163) is a very far cry from the elegant capital of contemporary bookhand, with its marked differentiation between thick and thin strokes101; it is a plain, unadorned hand, used for what is perhaps a heading.
Several of the letters bear an address written on the outside of the tablet. Usually this is written in elongated, thin and 'spindly' letters which we have called 'address script'. Examples are Nos. 21 (248), 22 (250), 23 (263) (lines 12-3), 25, 28, 30, 33, 34 (218) (the best example), 36, 40, 43 (325), 49, 50, and 106 (cf. No. 42 (324))102. Papyrus letters, from both Egypt and Dura-Europos, very occasionally have addresses on their outside and these too can be written in an enlarged script103; this can be quite similar to the 'address script' of the tablets, but the letters are usually made more like capitals. The letter-forms of addresses in the tablets are not very dissimilar in essence from the normal forms of the letters in ORC and we should perhaps regard 'address script' as no more than a variety of the standard cursive writing. Usually, a small portion of any letter is of no value in identifying it so that when, as is common, only a broken fragment survives it is generally impossible to make an accurate reading with any confidence.