But in the work now in progress of preserving these ruins from preventable decay and dilapidation, and of clearing away the block débris from the faces of the walls and the huge piles of soil débris deposited within the ruins by a long succession of explorers, both authorised and unauthorised, there have been within the last two years rescued from oblivion many important architectural features, the existence of which was altogether unsuspected by previous writers. Many of the interiors of the ruins are now exposed to view, thus enabling examinations, comparison, and measurements to be taken which before had been altogether impossible. Within the last eighteen months Zimbabwe has revealed many of the long-buried secrets of the ancient architects which were hidden from the eyes of Bent, Schlichter, and other scientific explorers of the ruins. Zimbabwe is stored with surprises for archæologists and antiquarians. Absorbing romance is buried deep below its floors. Its soil is richly charged with long-ungazed-at gold and prehistoric relics of high intrinsic value. The mysteries of the absence in Zimbabwe of any definite records in the form of inscriptions,[41] and also of the non-discovery within the Zimbabwe area of the burial-places of the ancients, have yet to be solved. It has quite recently been held by scientists at home that the late discoveries of ancient ruins in Rhodesia, with their classifications into types and probable time-sequences and periods of distinct forms of architecture, have so advanced investigations in this country that, until similar work has been carried on among such of the ruins of Southern Arabia as are believed to synchronise with, or be the architectural prototypes of, the earliest of the Rhodesian monuments, it would be idle to speak dogmatically as to the lands of origin of the succession of ancient builders and gold miners who toiled so industriously in this portion of South-East Africa. Still, but so far only as authentic discoveries have been made, the suggested occupation by the Sabæo-Arabians as outlined in chapter iii. of _The Ancient Ruins of Rhodesia_ affords for the present a good working hypothesis for the student in Rhodesia whose aim should be to closely watch the operations of archæologists and antiquarians in the land of ancient Yemen, while at the same time recording with the utmost exactness and fullest detail all and every possible architectural feature of such of the ruins in Rhodesia as may fall within the description of the First Period of Zimbabwe Architecture, of which the Great Zimbabwe is undoubtedly a most perfect example. This work will awaken the most piquant interest and fascination, for in this direction may be found the definite solution of our local problem as to which particular wave of the Semitic migrations is responsible for the erection of certain of our ruins.