PHILADELPHIA, April 23, 1861.

General SIMON CAMERON, Secretary of War:

DEAR SIR: The suspension of intercourse between this place and Washington has caused an intense feeling here in relation to the safety of the capital, and there is great eagerness to rush to its assistance. This anxiety, however, has not been participated in by the military authorities, and as yet there have been but few troops passed through to Havre de Grace. The people of Philadelphia exhibit some mortification that the Bostonians should have got nearly a week ahead of their troops, notwithstanding their greater distance from the scene of action.

After our communication with Washington was cut off via Baltimore in consequence of Mr. Garrett changing his plan of conveying troops through that city from a steam ferry-boat between Canton and Locust Point to the railroad through the streets, I immediately arranged transportation between Havre de Grace and Annapolis for five regiments per day. It seems, however, that the remaining New England and New York troops have for some reason taken the ocean route, and but few Pennsylvania troops are prepared to move. If the route from Annapolis to Washington City is open, we have transportation facilities now on the Chesapeake equal to the movement of fifteen thousand troops per day to your city, together with any amount of provisions, &c., for their support.

Sherman's battery arrived here last night, and could have been in Annapolis to-day. It is understood, however, that it will not leave until to-morrow morning, and then stop at Elkton. We infer from this that you must feel entirely safe at Annapolis and at Washington. Mr. Palmer informs me that you have not taken military possession of the Washington Branch of the Baltimore and Ohio Railroad Company and the Annapolis Road. If you have no superintendent fit to control such an enterprise, I would mention Joseph D. Potts, now in Baltimore, at the Northern Central Railroad Office, and T. H. Duprey, here. Colonel Small smuggled himself off without arms against my earnest protest and refusal to send him without them. He, however, got his force back without much damage to it.

Very respectfully, your obedient servant,

J. EDGAR THOMSON.

PHILADELPHIA, April 23, 1861.

Honorable SIMON CAMERON, Secretary of War:

DEAR SIR: Since I wrote my last of this date I have been informed that the Baltimoreans and Marylanders have destroyed the whole of the bridges on the Northern Central. This seems to have been a mere spite action, and must convince the Government that those loyal to the Government in Maryland are in a vast minority. As soon as the capital is safe from attack, it seems to me that the Government should at once turn on Baltimore and place it under martial law, and require that it should pay all damages to the railroads it has destroyed, and to their business.

There seems to be very little vigor in the organizing and dispatching of troops from this place. Who is to blame time must show. There is evidently a great deal of red tape to retard matters. Sherman's battery, which could as well have been in Annapolis to-day, is still here. I hope you will give them a stirring up. I have provided ample means