Our loss, by officers just from rear of column,is estimated at from 2,500 to 3,000. All beyond that we believe to be exaggeration. The retreat was covered by a good steady column, and the forts on south bank of Potomac are all strongly re-enforced with fresh troops.

T. A. S.

FORT McHENRY, Baltimore, July 22, 1861.

Lieutenant-General SCOTT, Washington:

Only the Wisconsin and two regiments from Pennsylvania, the First and the Fourth, have arrived. All of them yesterday and to-day. I think they are all needed here.

General Banks has gone to persuade the Sixth Massachusetts Regiment to stay, their time having expired. He goes to Harper's Ferry to-morrow morning.

JOHN A. DIX,

Major-General.

WASHINGTON, July 22, 1861.

Colonel SCOTT:

Please ascertain quickly if General McClellan's dispatch of last night,* containing three hundred and twenty words, was delivered to General Scott before he sent the dispatch sent in cipher to him last night by Mr. Westervelt.+ Important.

B. P. SNYDER.

[Indorsement.]

The long message was not received until after cipher message had gone.

T. A. SCOTT.

JULY 23, 1861.

General RUNYON, Alexandria:

Is the citizen steamer on the line to Alexandria? I have understood there was so great a rush of men on board from your wharf they would not go back again.

Can you not put a guard strong enough to preserve order there?

This boat is quite a convenience to us and the public.

The passage of all men properly authorized to go on board will be paid.

MANSFIELD,

Brigadier-General.

JULY 23, 1861.

Captain MOTT, Chain Bridge:

Liberate all the stragglers you have, and direct them to their respective camps this side of the Potomac.

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*Page 752.

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+Probably that on p. 752.