The progress and condition of the Post-Office Department will be seen by reference to the report of the Postmaster-General.  The extent of post-roads covered by mail contracts is stated to be 134,818 miles, and the annual transportation upon them 34,580,202 miles.  The number of post-offices in the United States is 12,553, and rapidly increasing.  The gross revenue for the year ending on the 30th day of June last was $4,262,145; the accruing expenditures, $4,680,068; excess of expenditures, $417,923.  This has been made up out of the surplus previously on hand.  The cash on hand on the 1st instant was $314,068.  The revenue for the year ending June 30, 1838, was $161,540 more than that for the year ending June 30, 1837.  The expenditures of the Department had been graduated upon the anticipation of a largely increased revenue.  A moderate curtailment of mail service consequently became necessary, and has been effected, to shield the Department against the danger of embarrassment.  Its revenue is now improving, and it will soon resume its onward course in the march of improvement.

Your particular attention is requested to so much of the Postmaster-Generals report as relates to the transportation of the mails upon railroads.  The laws on that subject do not seem adequate to secure that service, now become almost essential to the public interests, and at the same time protect the Department from combinations and unreasonable demands.

Nor can I too earnestly request your attention to the necessity of providing a more secure building for this Department.  The danger of destruction to which its important books and papers are continually exposed, as well from the highly combustible character of the building occupied as from that of others in the vicinity, calls loudly for prompt action.

Your attention is again earnestly invited to the suggestions and recommendations submitted at the last session in respect to the District of Columbia.

I feel it my duty also to bring to your notice certain proceedings at law which have recently been prosecuted in this District in the name of the United States, on the relation of Messrs. Stockton & Stokes, of the State of Maryland, against the Postmaster-General, and which have resulted in the payment of money out of the National Treasury, for the first time since the establishment of the Government, by judicial compulsion exercised by the common-law writ of mandamus issued by the circuit court of this District.

The facts of the case and the grounds of the proceedings will be found fully stated in the report of the decision, and any additional information which you may desire will be supplied by the proper Department.  No interference in the particular case is contemplated.  The money has been paid, the claims of the prosecutors have been satisfied, and the whole subject, so far as they are concerned, is finally disposed of; but it is on the supposition that the case may be regarded as an authoritative exposition of the law as it now stands that I have thought it necessary to present it to your consideration.