Castle Thunder, Richmond, Virginia. Dear Father:--By permission and through the courtesy of Captain Alexander, I am enabled to write you a few lines. You, who before this have heard from me in regard to my situation here, can, I trust, bear it, when I tell you that my days on earth are soon ended. Last Saturday I was court-martialed, and this evening, a short time since, I received notice of my sentence from Captain Alexander, who has since shown me every kindness consistent with his duty. Writing to my dear parents, I feel there can be no greater comfort after such tidings, than to tell you that I trust, by the mercy of our Heavenly Father, to die the death of a Christian. For more than a year, since the commencement of my confinement, I have been trying to serve him in my own feeble way, and I do not fear to go to Him. I would have loved to see you all again; God saw best not; why should we mourn? Comfort your hearts, my dear parents, by thoughts of God's mercy unto your son, and bow with reverence beneath the hand of Him who "doeth all things well." * * * I sent a ring to my wife by a clergyman, Monday last; I also sent a telegram to yourself, which will arrive too late, as the time of my execution is set for the day after to-morrow. Dear parents: there are but few more moments left me; I will try to think often of you; God bless and comfort you; remember me kindly and respectfully to all my dear friends and relatives. Tell Kitty I hope to meet her again. Take care of Freddy for me; put him often in remembrance of me. Dear mother, good-bye. God comfort you, my mother, and bless you with the love of happy children. Farewell, my father; we meet again by God's mercy. Spencer Kellogg. The following account of the execution is from a Richmond paper: "At eleven o'clock yesterday forenoon, a detail of one hundred men from the City Battalion, marched from Castle Thunder with Spencer Kellogg, the recently condemned spy, in custody. "The cavalcade reached the scene of execution about half-past twelve o'clock, where, as usual, a vast concourse of people, of both sexes and all ages, were congregated. After a few moments spent in preliminary arrangements, the prisoner was escorted, under guard, to the gallows. While seated in the hack awaiting the perfection of the arrangements for his execution, he conversed freely with the utmost _nonchalance_ with Dr. Burrows, frequently smiling at some remark made either by himself or the minister. "Arriving under the gallows, the charges preferred against the accused and the sentence of the court-martial were read. A short but impressive prayer was then offered by the minister, at the conclusion of which the condemned man, unaccompanied, mounted the scaffold.