The rediscovery of this almost forgotten book in which the author, the Danish publicist and anthroposophist Carl Vett, is telling of a forgotten time is a lucky coincidence. In 1925 I was in Constantinople, and was, so it was generally said, the first non-Mohammedan to be allowed to live for a time as a dervish in a Sufi monastery . Many years of study had made me familiar with the phenomena of psychic research, and I wanted to observe at first hand the ecstatic states attained by the dervishes in their way of initiation - for the dervish orders of Islam are schools of initiation. Before and during my stay with the dervishes I kept a diary. It was not intended for special publication, but in view of the execution of twenty-nine men, most of whom were sheiks or members of the Naqshbandi order . it has seemed that these experiences might be of more general interest; and so I have decided to offer them to the public. (From the author's foreword) Even now, more than 70 years after its initial publication, this book is a valuable read for anybody interested in the Islamic aspect of the mystical heritage of mankind.