The Life & Character of the Seal of Prophets (sa) - Volume II — Page xii
xii RH: An abbreviation for Raḥimahullāh , meaning, “May Allāh have mercy upon him,” is written after the names of deceased pious Muslims who are not Companions. In transliterating Arabic terms we have followed the following system: ا at the beginning of a word, pronounced as a , i , u , preceded by a very slight aspiration, like h in the English word ‘honour. ’ ث th , pronounced like th in the English word ‘thing. ’ ح ḥ , a guttural aspirate, stronger than h. خ kh , pronounced like the Scotch ch in ‘loch. ’ ذ dh , pronounced like the English th in ‘that. ’ ص ṣ , strongly articulated s. ض ḍ , similar to the English th in ‘this. ’ ط ṭ , strongly articulated palatal t. ظ ẓ , strongly articulated z. ع ‘ , a strong gutteral, the pronunciation of which must be learnt by the ear. غ gh , a sound approached very nearly in the r ‘grasseye’ in French, and in the German r. It requires the muscles of the throat to be in the gargling position whilst pronouncing it. ق q , a deep guttural k sound. ء ’ , a sort of catch in the voice.