This book was written in the early 1930 when people were saying that Kush was of Asiatic (not in metaphysical definition, lol) origin, oh wait they still say that today, oops!! lol.
But nevertheless five seconds later she says:
Arabia was originally settled by two distinct races, an earlier Cu****e Ethiopian race and a later Semitic Arabian. 'The Cu****es were the original Arabians and dwelt there before Abraham came to Canaan. Ancient literature assigns their first settlement to the extreme southwestern point of the peninsula.