Sentence:  The tribes of the Syrian Harrah may, of course, ultimately have come from Southern Arabia, or their home may have been near the borders of the South-Arabian empires, and their alphabet is no doubt to be derived largely from the so-called Himyaritic script ; for the history of the <WSD>ancient North-Arabian</WSD> alphabets seems to be that of a gradual remigration from Southern Arabia, beginning at a time when the Himyaritic alphabet had not yet received the form in which it is known to us. 
Meaning of the word marked with <WSD> tags:  A group of South Semitic abjads used in central and northern Arabia from the 8th century BCE to the 4th century CE