A Note on Transliteration This book uses a simplified version of the 2012 Library of Congress style of transliteration for Arabic (www.loc.gov/catdir/cpso/roman.html). Diacritical marks, such as macrons and underdots, have been omitted except for ‘ayn (‘) and hamza (’) when they appear in the middle of a word, e.g., Sanaʻa, Aden (rather than ‘Aden), Tha’er. Arabic plurals, both irregular and sound, are rendered simply with an “s.” Proper nouns with universally accepted English spellings are rendered accordingly. xv https://doi.org/10.1017/9781009272148 Published online by Cambridge University Press