poor ana rocny,Oapt. Morrison, with a detachment of menfrom the several companies computing the 12thregiment, went last week to “Sugar Loaf Mountain,’'and thereon the highest pan. of it builtau observatory to be used by the Federal forcesas a signal station. 1 had the pleasure of being one of the party. It is thirty-two feet high,ami has a base twenty feet square. It commands a view of nearly 150 miles. We couldfrom the top of the tower see distinctly four rebel encampments in old Virginia, one of which was at Leesburg.We have arrested quite a number of persons who have been engaged in giving intelligenceof our movements to the eneuiy. I think that we will learn them not to ‘'tell stories out of school'’ by the time we get through with them. The tower spoken of above we named in honorof our captain, calling it Morrison’s Tower.Lieut. Henry J. Austin of JN'ew Albany is one of the Bigual party stationed on “Sugar 1 Loaf.”