The Union has lost one of its ablest defenders, and Pennsylvania a noble, upright citizen, ever zealous for the public good. General Charles Ferguson Smith died at Savannah, Tennessee, on Friday last, from an illness contracted at the time of his occupation of that town. The deceased officer was a son of Dr. Samuel B. Smith, of Philadelphia. From the date of his graduation at West Point, in 1825, his advancement, not only in rank, but in the esteem and confidence of his fellow officers, was merited and rapid. Commencing his military career as a second lieutenant of artillery, his distinguished merit on the fields of Palo Alto and Resaca de la Palma, Monterey, Cherubusco, and Contreras, raised him in quick succession to the rank of Major, lieutenant colonel, and colonel. At the time of his death he was colonel of the Third Infantry—one of the best regiments in the service. Such worth as his could not lie dormant in the present struggle.—In August last he was made a brigadier general. At the taking of Fort Donelson his valor was conspicuous, alike to friend and foe, and won for him the rank of major general.