SAINT LOUIS, MO., December 19, 1861.

Brigadier General U. S. GRANT, Cairo, Ill.:

By what authority did you send back exchanged prisoners? They are not under assumed names. All were identified here before exchange.

H. W. HALLECK,

Major-General.

SAINT LOUIS, December 19, 1861.

Brigadier General U. S. GRANT, Cairo, Ill.:

No such man as W. H. Buel, colonel, known at these headquarters. It is most extraordinary that you should have obeyed a telegram sent by an unknown person and not even purporting to have been given by authority. The prisoners will be immediately returned to Cairo.

H. W. HALLECK,

Major-General.

HEADQUARTERS DISTRICT OF SOUTHEAST MISSOURI,
Cairo, December 20, 1861.

Major General H. W. HALLECK, U. S. Army,

Commanding Department of the Missouri, Saint Louis, Mo.

GENERAL: Your second dispatch saying "It is most extraordinary that you should have obeyed a telegram sent by an unknown person and not even purporting to have been given by authority" is received. In justice to myself I must reply to this telegram. In the first place I never thought of doubting the authority of a telegram received from Saint Louis, supposing that in military matters the telegraph was under such surveillance that no military order could be passed over the wires that was not by authority; second, the signature to the telegram was made with so many flourishes that I could not make it our at all and to send a copy to your headquarters was obliged to send to the office here for a duplicate; third, before this telegram was received Captain Livingston who came in charge of these prisoners reported to me that several who were to come had proven to be impostors and that he had reason to believe that two of those still with him were under assumed names; fourth, directions sufficient to detain prisoners (Camp Jackson exchanged prisoners) might come from the provost-marshal's office, from General Curtis or from headquarters, and I do not know the employees of the former nor the staff of the latter. The fact is I never dreamed of so serious a telegraphic hoax emanating through a large and responsible office like that in Saint Louis. Inclosed I send you copy of the dispatch received.

I am, general, very respectfully, your obedient servant,

U. S. GRANT,

Brigadier-General, Commanding.

[Inclosure.]

SAINT LOUIS, December 15, 1861.

General GRANT:

The D. G. Taylor left here at 1 p. m. to-day. Stop her and send back all the Camp Jackson men. They all have assumed names.

W. H. BUEL,

Colonel.