Turkish religion, history and folklore, in particular two of some length dealing respectively with the little known heretical sects of Islam in Turkey and with the real and alleged examples of the transference of Holy Places from Christianity to Islam.
"For the field, which Hasluck made peculiarly his own, he was well equipped. He had a wide knowledge at first hand of men and things in the Levant. His lively interests, his linguistic gifts and his compelling friendliness were irresistible; he was liked wherever he went and by all sorts and conditions of men whatever their race or creed. This faculty enabled him to gain at first hand information which is not readily given to a Frank and a Giaour. To this intimate personal acquaintance with the modern Levant he added an amazing knowledge of the records of the earlier travellers, and for many years his holidays in England were devoted to mastering the unpublished MSS. of Levantine travel in the British Museum.
"The fruit of this dual equipment is to be seen in the very important work upon Transferences. His knowledge of the travellers' records enables him to trace the varying fortunes of the rival religions at specific holy places in a definite chronological series. A good deal of hypothesis as to the conditions of the transference of Pagan to Christian and Christian to Mohammedan cults, which is at present lightly accepted, is shattered by a remorseless statement of specific facts. And for the wider study of religious contacts Hasluck's researches have a definite value providing, as they do, the analogy of ascertained facts in a particular area. This Hasluck himself realised. During his last three years of indomitable struggle with a fatal illness in France and Switzerland, he read widely on the hagiology and local cults of Western Europe. His letters to his friends were full of penetrating suggestions inspired by his excursion into this new field and indications of the problems, which the application of the principles derived from his study of the local cults of the Near East suggested or solved. But illness, which could not dull the energy of his mind, prohibited the physical labour of working out his material in detail and except for a few brief fragments this, which would have been the most interesting and suggestive chapter of all, remained unwritten.