GRETNA, on the same shore, is nearly two miles further up the river, and stands opposite Lafayette. The whole distance is spotted with comfortable residences, principally inhabited by the owners of the adjoining grounds, and the walk from Algiers to this village is very gratifying to one partial to such exercise. There is a steamboat constantly plying from here to the city, which affords a desirable excursion of nearly three miles, touching at Lafayette in its passage each way. The village has a rural appearance, is regularly laid out, and exhibits some neat tenements. The forest approaches quite near; and, the idea that one may so easily lose himself in the neighboring woods, gives to the place a touch of romance which only the denizens of a crowded city know how to appreciate. From the great number of cattle observed along the shore, it would seem as if there was no necessity of diluting the milk for the New Orleans market, unless the milkmen be tea-total temperance men, and take this method to introduce the inhabitants gradually to a taste for water. THE RACE COURSES. There are three of these in the vicinity of this city. The _Louisiana_, near lake Pontchartrain; the _Metairie_, near the Shell road; and the one at Carrolton. These are as well patronised as any in the country, and, in the racing season, the inhabitants of the neighboring states, from a great distance, flock hither to participate in the sports of the turf. Much praise has been bestowed upon the arrangements on these occasions. Even here, as in many other countries, the ladies, by their presence, have given them countenance and encouragement--and the course usually is "gemmed by the rich beauty of the sunny south." THE BATTLE GROUND, (formerly known as "the Plains of Chalmette,") the very naming of which causes the bosom of an American to swell with patriotic pride, lies five miles below the city. It may be approached either by the Grand Gulf rail-road, or by a good highway along the levee, the new Convent and United States barracks being within full view. But first it may be necessary to look briefly at the historical facts which give celebrity to the spot. Early in December, 1814, the British approached New Orleans, about 8000 strong, by the way of the lakes Borgne and Pontchartrain. Their passage into the lake was opposed by a squadron of gun-boats under Lieut. Jones. After a spirited conflict, in which the killed (500) and the wounded of the enemy exceeded the whole American force, he was compelled to surrender to superior numbers.