Baden, Austria, July 28, 1858.

Our steamer left Odessa at six P. M., and the next morning at sunrise we found ourselves at the entrance of one of the mouths of the Danube, with Sulina, the Turkish port, at our left, a small ill-built wooden town, its position reminding me of the Balize at the mouth of the Mississippi, with low banks and marshy soil, covered with reeds and rank vegetation. Large numbers of vessels lie straggling along the wooden wharves, waiting for a favorable wind, and tug boats to tow them up to their destined ports for cargoes of grain.

We had but few passengers; among the number was a Georgian Princess, the grand-daughter of the last King, whom I had met with her husband, a Russian colonel, in their own country. This lady is the sister of the Princesses taken captive by Schamyl, who were ransomed by the Russian government, as mentioned in a former letter. The meeting was the more agreeable, because quite unexpected. The society of a young and beautiful Georgian woman, with all the simplicity and amiability of the lady, speaking the English and French language fluently, as well as her husband, a man of large experience in Circassia, was calculated to make a long trip less irksome than it would otherwise have been.

At four P. M. we arrived at Galatz, in Moldavia, a city of some forty thousand inhabitants, where we changed steamers, remaining there thirty-six hours, awaiting the arrival of the passengers from Constantinople.

A larger boat was now furnished, constructed after the manner of our American river boats, with a saloon on the main deck, abaft the wheels, an upper promenade deck, and a number of cabins upon the forward deck. Our numbers being considerably augmented, the heat was oppressive, and mosquitoes brought back reminiscences of the Alabama and Apalachicola in the spring time.

We landed at Giurgevo, in Wallachia, a small town, the port of Bucharest. Both Galatz and the place named lie upon the river bank, but the principal parts are upon bluffs above. Galatz has a mixed population of all races. As the Principalities are subject to Turkey, the coin of that country is in use, as well as that of all the neighboring states, and the numbers of money-changers installed at short intervals upon the sidewalks, present a curious spectacle.

The language has much of the old Roman in its composition, and one is struck with the names of streets and persons upon signboards bearing analogy to the Italian. The dresses of the peasants also struck me as resembling those worn in Italy. The original inhabitants were evidently Romans. Their sympathies are, however, more Russian, as they profess most generally the Greek faith.

The river is quite serpentine in its course, and the scenery as we advanced became more varied, groups of forest trees and better cultivation being seen. Turkish villages lie along the left banks with their mosques and minarets, and Wallachian and Moldavian villages on the right.

We passed Silistria, celebrated for its defence by the Turks and defeat of the Russians with a loss of twelve thousand men; landed and received passengers at Mikopol, and at the strongly fortified town of Widdin, and arrived at the Eisernen Thor, or Iron Gate, where the low stage of water obliged the landing of passengers, and we took wagons for the distance of a few miles and found a small steamer of light draught of water, which conveyed us through the pass between high mountains of the boldest and most romantic scenery, a miniature Switzerland, to the town of Orsova, the frontier line of Hungary. Here all the luggage was discharged and carried to the Austrian Custom House for examination. Tobacco, sealed letters, and playing cards were handled without mercy, and some of the passengers had to pay heavily.

We made a halt at Belgrade, the last point in Turkey, and at Semlen near the mouth of the Save. The Hungarian shores were alive with cattle, horses, and sheep grazing.