Preliminary explorations had been made by various scientific societies, as for instance that of John M. Parker, F. G. S., F. R. G. S., under the auspices of the Royal Geographical Society and the Society for Promoting Christian Knowledge, in 1839-40. They went overland from Constantinople to Cæsarea, Malatia, Diarbekr, Mosul, Koordistan, Bitlis, Marash, Erzerum, Trebizond, and thence back to Constantinople. The report of this extended tour through Asia Minor, northern Mesopotamia, Koordistan, and Armenia, published in two volumes, under the title “Travels and Researches in Asia Minor, Mesopotamia, Chaldea, and Armenia,” was of great value to the missionaries in planning their locations. These researches were made largely from the purely scientific standpoint and in some cases needed to be supplemented by missionary observations. The establishing of mission locations over the vast areas of Asiatic and European Turkey was not hastily carried out. The country was well mapped and explored before the stations were opened, and then only such places were chosen as promised to be central to large populations and healthful for missionary residences. The policy seems to have been early adopted to set the stations far apart, with two or more missionary families in each of them. The success of this plan has proven its wisdom, and even now the tendency is to greater consolidation in important centers rather than to a scattering of forces. A few, and but a few, places early opened as stations were later abandoned. Three of these were Mosul, Diarbekr, and Arabkir. The former place proved to be exceedingly unhealthy and was made an outstation of Mardin, while the two latter places were within one hundred miles of Harpoot and were made outstations. The carefulness and foresight with which the early stations were chosen are proved by the test of over fifty years of successful occupancy. Trebizond, upon the southern shore of the Black Sea towards its eastern extremity, was occupied as a station, as already stated, in 1835. It is a large city of great influence, with a Greek, Armenian, and Turkish population. In 1839 a missionary family was sent to Erzerum, one hundred and ten miles into the interior to the southeast of Trebizond. As soon as these stations were opened they became the centers of exploration for securing and forwarding information to the headquarters of the missions in Constantinople and to the Board in Boston.