A gentleman, who is a prominent statesman, recently seriously advised me not to think of establishing a line of mail steamers between the United States and Brazil, for the accommodation of the hundreds of sailing vessels engaged in that trade, but to get up a mammoth company and run five or six thirty thousand ton steamers, like the Leviathan, between Norfolk and Rio de Janeiro. He said that the increased size of the steamer would enable me to carry freight cheaper than sailing vessels. The reasoning was neither very clear nor convincing to me on behalf of the mysterious capacities which he attributed to large steamers. I suggested that, in the first place, there was no cargo passing either way between the United States and Brazil which could afford to pay steam transportation under any circumstances; that so large a cargo could never be obtained at once in Rio de Janeiro or elsewhere; that the merchants of this country did not wish it all landed at one place; that it would cost as much to remove it from Norfolk to the place of consumption, as it would from Rio de Janeiro to its final destination; that they did not wish it delivered all at once, but in small lots at a time, and distributed where it was needed; and that, even if it were at all practicable, which no business man could for a moment believe, the people would not be willing to have a fruitful field of industry in shipping occupied by some great overgrown company, with a great coffee monopoly, which would surely follow. Too much has been expected of large ships. The clipper "Great Republic" is not freighted half of her time. The "Leviathan" can not pay in freighting unless she runs to Australia and the East-Indies, and runs slowly, on very little coal. She may do very well with a voluntary cargo, which will load and unload itself in a hurry, such as a cargo of emigrants, and not steaming at too a high a speed. But it would require a dozen steamers as tenders to bring these emigrants from Ireland, Bremen, Havre, Hamburgh, Amsterdam, and other European cities, to her central depot in England. She would, however, become a most useful if not indispensable transport vessel for the British Government.