hundred short, plebeian, often half-barbarous, very old inscriptions on
a collection of ollae. The k before e, or any letter except a, is
solecistic, just as in no. 831 is the c, instead of k, for calendas.
From this I would infer that, as in the latter the writer saw no
difference between C and K, so to the writer of the former K was the
same as C before E."

Again he says:

"And finally, what is to me most convincing of all, I do not well
understand how in a people of grammarians, when for seven hundred years,
from Ennius to Priscian, the most distinguished writers were also the
most minute philologers, not one, so far as we know, should have hinted
at any difference, if such existed."

As to the peculiar effect of C final in certain particles to "lengthen"
the vowel before it, this C is doubtless the remnant of the intensive
enclitic CE, and the so-called 'length' is not in the vowel, but in the
more forcible utterance of the C. It is true that Priscian says:

[Keil. v. II. p. 34.] Notandum, quod ante hanc solam mutam finalem
inveniuntur longae vocales, ut _hoc_, _hac_, _sic_, _hic_ adverbium.

And Probus speaks of C as often prolonging the vowel before it. But
Victorinus, more philosophically, attributes the length to the "double"
sound of the consonant:

[Mar. Vict. I. v. 46.] Consideranda ergo est in his duntaxat
pronominibus natura C litterae, quae crassum quodammodo et quasi geminum
sonum reddat, _hic_ et _hoc_.