Fourth Centre. Baltimore.

Around Philadelphia, in addition to the great works extending to Columbia, Amboy, and Baltimore, already mentioned, are 1. The Trenton railroad; 2. The Norris-town and Germantown road, designed for passengers and for the accommodation of some manufacturing villages, such as Manayunk, 16 miles in length; and 3. That of West Chester, a branch of the Columbia railroad, 9 miles in length, designed for the supply of the markets of the city. There are also several railroads running through the city, of which the rails are laid on the level of the street, and on which horse-cars only are used.

Beside the Baltimore and Ohio railroad with its Washington branch, Baltimore is also about to have a railroad through York, to the Susquehanna, opposite to Columbia, the length of which will be 73 miles. The object of this road is to contest with Philadelphia the commerce of the valley of the Susquehanna. The Pennsylvania canal with its various branches forms a canalisation of this river and its tributaries above Columbia. But below Columbia, there are several rapids and shoals which interrupt the navigation of the river, except for downward-bound boats in the highest stages of the water. The Philadelphia merchants, fearing that all the works executed at a great expense by Pennsylvania, would turn out much less advantageously for them than for the Baltimoreans, as these last have, indeed, openly boasted, opposed for a long time both the canalisation of the Susquehanna from Columbia to its mouth, and the permission to construct that section of a railroad from Baltimore to Columbia, which would he within the limits of Pennsylvania. Their opposition has, however, been at last overcome, and charters have been granted authorising the construction of both works. The railroad company, to which Maryland has just made a loan of 1,000,000 dollars, is pushing on the railway with great activity.