that there are now places on the south side of the Ohio River, such as Louisville more exposed to raids from the rebels, and which should be fortified in preference. For these reasons and because the Ohio River itself, especially with the said of gunboats, is a very considerable defense, and there does not seem any pressing demand for immediate action, I do not see that the General Government is called upon at this time to commence the works proposed by the colonel.

DEFENSES OF THE KENTUCKY CENTRAL RAILROAD.

The defenses of this road, consisting mainly of the stockades to defend the bridges, and Ford Robinson (a small star redoubt) at Paris, nearly completed, and Fort Clay at Lexington, now that the former have been in a manner made proof against shells by the excavation of an underground apartment under a timber floor, and the ditches made capable of defense by infantry, are in an admirable condition. In inclose herewith a map* of the railroad from Benton Station to Lexington, a distance of 80 miles, with plans of the stockades and their location.

ROUTE OF THE ARMY INTO EAST TENNESSEE UNDER MAJOR-GENERAL BURNSIDE, COMMANDING THE DEPARTMENT.

Since writing the foregoing, I have received a report from Captain O. M. Poe, chief engineer Twenty-third Army Corps, dated Knoxville, Tenn., September 4, as follows:

Having been constantly on the march, I was compelled to delay until to day the writing of my monthly report.

I continued the work upon the fortifications at Hickman (Camp Nelson) from the 1st August until the 13th, on which day I relinquished charge to Assistant Gilliss, designated by you to relieve me. Up to that date 5,000 days' work had been expended upon them; and Fort Nelson was in a state of efficiency, while Fort Jackson was in a forward condition. The heavy rifle trenches connecting the two were almost complete, while some progress had been made upon the battery to the eastward of Fort Jackson.

On the 14th of August, I left with the headquarters of the Twenty-third Army Corps. Our march from Lexington, via Somerset, Ky., Smith's Ford, Ky., Pine Knot Tavern, Ky., Chitwood's Tenn., Montgomery, Tenn., to Emery's Iron-Works, thence to Lackey's, thence, via Campbell Station, to Knoxville, where we arrived to-day, was a toilsome one, made over rough roads, and with some loss (though slight) of transportation. The itinerary of the route comprises a vast deal of information, of which a concise statement will be made as soon as I can get the time and opportunity to write it out. This much I can say now: the maps which we have are perfectly worthless, nay, even worse, as they only serve to mislead.

It affords me pleasure to be able to say that the Engineer Battalion was of great assistance on the march, clearing and mending the road, making it passable where it seemed almost impassable. This was particularly the case at Smith's Ferry or Ford over the Cumberland River.

Major Sidney S. Lyon, Fourth Kentucky Cavalry, assistant engineer, was with me in the discharge of his duties during the whole march.

Assistant J. H. Brooks proved himself of great value, and I would respectfully recommend a further increase of his salary to $120 per month.

He is certainly worth as much to the Government as a first lieutenant of infantry or a second lieutenant of cavalry, and the duties he performs are of so arduous a nature in the field as to fully entitle him, in my opinion, to the salary I recommend. It is but simple justice.

The incidents of the march, being matter more fitted for the itinerary than for the report, are reserved for a future communication.

I would also commend in warm language the zeal and efficiency of Private Moore, who has had charge of the odometer.

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

J. H. SIMPSON,

Major, Corps of Engrs., and Chief Engr., Dept. of the Ohio.

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*Omitted.

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