I visited the Alexandria museum over the market house, and among the collection there, I saw the mantle in which George Washington was christened; his masonic robes, apron and gloves; his pistols, presented to him by Louis XVI; a model, in stone, of the Bastile, presented to him by the national assembly of France; his pack-saddle, used in the revolutionary war; his flag, borne by his body guard in that war; the first British flag, captured in that war, called Alpha by Washington; the last flag taken in that war from Cornwallis; La Fayette’s flag--blue; Decatur’s flag; Paul Jones’ flag, on board the Bonne Homme Richard, in his battle with the Serapis; Gen. Morgan’s flag, borne by his Virginia regiment; and a great many other relics of revolutionary times. General Washington’s letter to the cotillion party, which used to assemble in the house where I am located, is in the museum. In this letter the General declines to meet with them, on account of Mrs. Washington’s age. What thrilling recollections of times gone by, do these relics stir up within us? What a crowd of emotions, of all sorts, rush upon the mind, when looking on these memorials of former days, former ideas and opinions? of old customs and ancient manners, compared with modern ones? We live in a world that is passing away--in its habits, customs, dress, weapons of warfare; all is changed, changing and never will be stable, scarcely an hour! Ninety-four years ago, this spot, where this city is, was surrounded by a dense forest, on the verge of civilization, now it is quite on the eastern side of our domain. There is a large market house here, of brick, over which are rooms for the several public offices, and in the third story is the museum. The mayor, clerk, auditor, &c. have their offices in the first story above the market house. The market is well supplied with meat, fish and vegetables. I saw too in it many flowers and small evergreen trees, in a proper state for planting them. The vegetables, flowers and trees were offered at very low prices--hardly sufficient to pay for bringing them to market. Those who brought them appeared to be poor, with families to support. The rail-road from Cumberland to Baltimore has injured Alexandria, by taking some of the trade of the upper country away from this district. An extension of the canal to this city will bring back some of the trade which it has lost temporarily. The water in the wells of this city is not good, except a few in the suburbs, from which the city is well supplied. By taking the water out of the canal, it can be easily conveyed to the houses and supply all the citizens with healthful water.