From BELGIUM intelligence has been received that a convention has been concluded between the Belgian and Dutch governments for the amalgamation of the railways of the two countries. The great trunk line beginning at Antwerp will be continued to Rotterdam, and so be put into communication with the whole of the Netherlands. It is stated, upon good authority, that the Bavarian government has engaged to pay 1,400,000 florins to the administration of the Palatinate Railway, on condition that the latter shall undertake to execute the works on the line from Ludwigshafen to Wissemburg speedily. This is the point to which the Strasburg Railway is to be continued beyond the French frontier.----A change has occurred in the Belgian Ministry. The commercial regulations between France and Belgium are placed under the _régime_ of the common law, the treaty of 1845 not having been renewed. From TURKEY we learn that Mr. MARSH, the American Minister, left Constantinople on the 30th of July for Athens, whither he goes to investigate the circumstances attending the arrest and imprisonment of the American missionary, Dr. KING. Previous to leaving he had an audience with the Sultan.----Numerous and very destructive fires have recently occurred in Constantinople--two or three thousand houses having been burned.----Fresh and interesting discoveries are said to have been made at Nineveh by M. Place, the French Consul at Mosul; he is said to have found a series of paintings upon marble in vermillion and marine blue.----Steam navigation has lately increased greatly at Constantinople. More than twenty steamers now ply daily in the Bosphorus and the Sea of Marmora. It is said that a Russian company is about to be formed, which will have twenty vessels to run in opposition to these now established. Editor's Table. The Sabbath presents the most purely religious, and, at the same time, the least sectarian of all moral questions. It has, however, been generally regarded under two aspects, and defended on two distinct if not opposing grounds. One of these may be called the Scriptural or theological, the other the physical or secular. One class of advocates would lay the greatest stress on its divine appointment, the other upon its worldly advantages. One would magnify its ecclesiastical, the other its political and social importance. Without entering at length upon either of these arguments, in our present editorial musings, it is enough for us to state that those who would defend it as a permanent divine institution, rely mainly on the remarkable passage in Genesis announcing the divine rest from creation, and the sanctification of the seventh period of time, the Fourth Commandment as confirmatory of the same, and the early and continued example of the primitive Christian church, as evidence of a divinely-authorized change from the seventh day of the Jewish calendar to that on which Christ rose from the dead.