The distance from Cape Santa Maria, the entrance of the La Plata, to Buenos Ayres, is 200 miles: but the navigation is very dangerous, owing to rocks and shallows. In consequence of these dangers, large vessels generally come to an anchor every night in sailing up, and on the most moderate days it is necessary to be very vigilant, owing to the sudden effects of the blasts from the plains. After arriving within three leagues of the city, the cargoes are put into light vessels, and the ships go to the bay of Barragan, about twenty-four miles below, to refit and wait for freights. The principal streets of this town are the Calle de la Santa Trinidada, and the Calle de San Benito. The former runs almost the whole length of the city, and is occupied by the richer classes, who have also splendid villas in the country; almost every house has a garden both before and behind, and many have balconies latticed for odoriferous shrubs and flowers. The interior of the houses display great wealth, but not much cleanliness; and in summer they cover their floors with fine Indian matting, and in winter with carpets. The gardens are watered by small canals, and there is generally a large basin or reservoir in each, from which water is conducted by pipes into the houses. That part of the city inhabited by the negroes and castes has a very mean appearance, and, being very dirty, presents a great contrast to the external show of the other parts. The churches are covered with cupolas and steeples, which give them a handsome look, and the town-hall is a fine building in the great square; the convents, nunneries, the hospital for men, that for women, and those for foundlings and orphans, being edifices of stone, of a beautiful whiteness, which is quarried in the plains near the city.