Grotefend thought he found four and St. Martin six signs for _e_, but Burnouf correctly excluded that letter altogether from his alphabet. He, however, incorrectly admits one sign for _ô_ long. He considers the absence of _th_, a form that occurs frequently in Zend, is probably due to the scarcity of documents. The want of the palatals, _tch_ and _dj_, may perhaps be assigned to the same cause; though more probably it arises from the nature of the alphabet itself, for these letters are only developments of the consonants _k_ and _g_.[408] Burnouf acknowledges his obligation to Grotefend for twelve letters; but these should properly be raised to fifteen.[409] The twelve he admits include eight correct values and four incorrect. The three he leaves unacknowledged are _t_ (24), _u_ (36), and _a_ (41), all of which are correct, and they raise the number of correct values accepted from this source to eleven. Burnouf attributes three of his letters to St. Martin, namely _t_, _u_ and _i_: the first two are already accounted for from Grotefend; the _i_ is indeed due to St. Martin, but it is wrong. Burnouf rejected the only absolutely correct value found by St. Martin, viz. _v_. Two letters, the _m_ and _n_, he refers to Rask, from whom also he must have derived the _q_ (25) which he erroneously substitutes for Grotefend’s _k_. The twelve values which Burnouf credits to his own account include the _a_ of Grotefend and the _b_ of Münter.[410] There remain the two values which he was the first to fix correctly, viz. _k_ (4) and _z_ (18); the others are all incorrect. We have thus accounted for twenty-nine signs out of the thirty of his alphabet;[411] the other, the _ng_ (28) of Grotefend, he treated as uncertain, but suggested _h_, the true value being _j(a)_[412] Besides the thirty just mentioned he gives three other signs, to which he hesitates to assign any value, though he thought they might all represent the sound of _gh_. These are, as we have already explained, the _dj_ (32) and the ‘_k_?’ (33) of Grotefend, now ascertained to be _j_ before _i_, and _m_ before _u_. The other does not appear in Niebuhr’s list, and Lassen is the first to assign it a value, _g_, which turned out correct (_g_ before _u_).