The big states founded by Oguz Han lasted thousands of years. The alphabet he prepared was also used for thousands of years. Exactly when this alphabet fell out of use is not known, but there is an 18^th century lamentation for it named “Beautiful twenty five” by the poet Sheydai:          

How pleasing sounds to ears,

Saying all the beautiful twenty-five.

Some with tuneful voice, the vowels,

I followed all the beautiful twenty-five.

Seven were made of voice,

And eighteen contained noise,

After three thousand years of life

Why let yourself go, all the beautiful twenty-five?

Oh, Sheydayy says, Worse happened,

Alas, all the folk mourn, lament for you,

Now they scorn you,

Thus vanished, all the beautiful twenty-five

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