A. T. REYNOLDS.--The largest bell in the world is the "Czar Kolokol," or King of Bells, cast in Moscow in 1734, during the reign of the Empress Anna. It is 21 feet high and the same in diameter, and weighs 193 tons. During a fire in 1737 it fell to the ground, a large piece being broken out in the fall and remained sunk in the earth until 1837. In that year it was raised and now forms the dome of a small chapel made by excavating the space below it. The worshipers enter through the opening where the bell was broken by the fall. It is very unlikely that any attempt will ever be made to restore it to its former use. H. O. A.--In light oak graining, the ground coat is yellow ochre and the graining coat raw umber. House painters are not thoroughly agreed on graining for oak and walnut, so that they do not always mix the same shades; in fact, since there is no school of house painting, it is largely a matter of individual taste and skill. T. P.--The first and second volumes of GOLDEN DAYS, being out of print, are not for sale at this office, and naturally command a premium when sold by other parties. Bound volumes are usually quoted at ten dollars, and higher prices may have been given. They may be had, however, occasionally through the medium of our exchange columns. A SUBSCRIBER.--1. The U.S. navy now has 116 vessels of all kinds, of which 44 are building or not in commission. 2. The greatest war ship of the English navy, and also the greatest in the world, is the Royal Sovereign, 380 feet in length, 75 feet in breadth, and of a displacement of 14,150 tons. The armament consists of four 13-1/2-inch guns, ten 6-inch quick-firing guns, and twenty-five 6-pounder and 3-pounder machine guns. DON'T KNOW.--Upon meeting a young married woman, upon her return from her wedding journey, it would be proper to congratulate her and wish her happiness in her new relation; but, if you had not previously known her in a single state, a simple acknowledgment of the introduction is all that would be necessary. ARCHY TECT.--A knowledge of geometry is essential to a successful architect; in fact, he should be expert in all branches of mathematics, as well as a good draughtsman. See answer to "Arch-I-Tect," in No. 42, Vol. 13, for your other questions, to which it is only necessary to add that architects are paid according to contract only. J. B. McF.--A tun is a certain measure for liquids, as for wine, and its capacity equals two pipes, or four hogsheads, or 252 gallons. Being a measure, a tun may be made of any shape, so that the capacity is neither increased or diminished. Any school arithmetic treats of this subject under the head of "measures."