Tiis EffBCT.—Col. Heg of tho 15th (Scandinavian) regiment, in a recent letter to Gov. Salomon, says:tiOar men are in good health and spirits. There is nothing heTe to dampen the ardor of our men, excepting the treason and disloyalty exhibited by the Peace Democracy at the North. ^ It is having a very'disbeartoniog effect in some regiments,”