"An elaborate series of grunts and gestures"

More in the weird colonial-era language books series - this time "The Siwi Language", by W. Seymour Walker, F.R.G.S (Late Royal Artillery), with a foreword by His Excellency Wilson Pasha (Governor, Western Desert Province of Egypt), 1921:

There are no interjections in Siwi which are sufficiently constant to be worth committing to paper.
Their meaning is expressed by an elaborate series of grunts and gestures which can only be acquired by practice.

And:

There is only one noun-adj. in Siwi in which the masc. and fem. forms are identical:
zlèta, naked, bare
Note 30. This exception is a good example of the construction of the Siwi vocabulary, and illustrates one of the reasons for its paucity. Amongst the women a naked female is quite a possibility, but to the general Siwani mind, it is so inconceivable, and so contrary to all established customs, that no special word-form has been evolved to cope with such an obvious phenomenon.

If you want to hear what Siwi is really like, the indefatigable Madi has put a Siwi audio file up on Tawalt: the Story of Prince Sayf. With a bit of help from books like Walker's (and more usefully Laoust's), I can make out a fair bit of it. Remarkably, Siwi has borrowed Arabic's comparative form, as you can hear in the second sentence.