tributary of the Potomac. The country in this vicinity is exceedingly abrupt, and its small ravines are filled with marshes and stagnant pools..

The soil consist of tenacious clay, is cold, and, in consequence of retaining moisture a long time, the camps are most always in an impassable condition, on account of the tenacious mud produced by the slightest agitation of the soil. Anywhere on these camping grounds a tent pin when driven in the ground brings water. In a sanitary point of view we cannot but regard these camping grounds as exceedingly unhealthy, owing, no doubt, to their close proximity to the river, to the low marshy grounds around about the camps, and to the peculiar nature of the soil..

The division has occupied these grounds but ten or fifteen days, not long enough to affect the health of the command as yet materially; but it is our opinion that if the command occupies these grounds for any length of time sick report will be increased twofold from local causes alone..

There is another very serious objection to occupying these grounds; as there are approaching indications of increasing sickness in the division, there will be no hospital accommodations for the sick short of Washington, and as the roads are now nearly impassable from the deep mud, it will be impracticable to transport the sick either to Frederick or to Washington without much suffering..

At present the health of the division is remarkably good, and the immunity from disease which the whole division has enjoyed for the last two months is without parallel in our armies. During the month of September the mean strength of the division was little less than 16,000, and the number of of deaths from disease alone was 16. As far as the regimental sick reports for the month of October have been received, they go to show that the command was equally as healthy..

The prevalent diseases now in camp are measles (a few cases), mild forms of intermittent and other fevers, and catarrhal affections. but typhoid pneumonia may be expected to prevail to a great extent soon, if the troops occupy these same camping grounds much longer..

We next proceeded to examine the medical topography of the country in Frederick County, in the vicinity of Frederick. On the eastern slope of the Blue ridge, some 4 miles northwest of the town of Frederick, we found the face of the country presenting a more favorable aspect for a large encampment. For several miles along the bade of the Blue Ridge the country is gently undulating, affording beautiful slopes for camps, and being well protected from the prevalent cold northwesterly winds by the Blue Ridge range. These grounds are well timbered, with oak openings, and abundantly supplied with numerous streams of good water..

The soil of these grounds differs materially from that of Rockville or the grounds occupied by General Banks' division. It is composed of sand and clay (argillo-arenaceous) and in covered with flint, indicating the soil to be hard, dry, and warm..

The prevailing winds, as above stated, are from the northwest, but being so well sheltered by the high ridge in the rear and receiving the morning sun, these grounds cannot but be well adapted to the health of troops..

The town of Frederick contains between 7,000 and 8,000 inhabitants. There are in the city many fine buildings suitable for hospital purposes, and if occupied for these purposes would obviate the necessity of sending the sick and wounded to Baltimore and Washington, although if necessary they could easily be conveyed to the above cities in a few hours by railway..