THE MEXICAN GULF RAIL-ROAD, runs from Elysian Fields street, on Good Children street, towards Lake Borgne. There are twenty eight miles of this road now in operation. When finished, it will afford considerable facilities to commerce, besides great benefit to the citizens, conveying them, in about one and a half hours, to the refreshing breeze of the ocean--where fish, oysters and game may be found in abundance. No doubt it will compete with the most favored watering places of Bay St. Louis, Pass Christian, Biloxi, &c. It will also be a great accommodation to the planters in the neighborhood--who already, so far as it goes, have given it good encouragement. This road has recently been purchased of the State, by A. Gordon and Co., who, availing themselves of about 22 miles of the Nashville rail-road iron, are bringing this work to a rapid completion. THE ROAD OF BAYOU ST. JOHN, which follows the sinuosities of that stream, and reaches lake Pontchartrain at the site of the old fort St. John, after travelling the distance of about six miles, presents a very pleasant drive. Returning by the new Shell road before mentioned, it varies the route without adding much to the distance. MACDONOUGH stands on the banks of the river opposite to New Orleans; and the crossing, in the hottest weather, is generally accompanied by a slight breeze, rendered cool and pleasant by the mighty current of the river, which comes from the icy springs of the Alleghanies and the Rocky mountains. The village, of itself, possesses no great beauty--but the country, the beautiful country is all around--and the noise and confusion of the city no longer annoy you. The great attraction at this spot is in visiting the United States marine hospital, one of the handsomest structures in Louisiana, which stands a little above. ALGIERS adjoins, and seems a part of Macdonough. This is the great work-shop of New Orleans, for the building and repairing of vessels. It has its dry docks, and other facilities for the most extensive operations. In business times, it presents a scene of activity that is seldom observed in any other part of these regions, and reminds one of the bustling and enterprise of the North. The period has been when Algiers prescribed the law, _vi et armis_, to the city itself--but the day and the disposition, have happily long since passed away.