A bill was introduced late in the session of the Congress which has just adjourned proposing to allow business-men to send out circulars or letters, with return envelopes, on which prepayment shall not be compulsory, but may be collected of the firm sending them out when returned to them. It is claimed that the postal revenues would be increased $30,000,000 per year. Probably the bill will be heard from next winter. Senator Cullom proposed that the printing of the postage-stamps be transferred to one of the bank-note companies. This would be a move in the right direction, as the government manufacture of the present issue has not been a success. O. H. SCHELL.--The ordinary English stamps were printed in sheets of 240. Each, stamp was different as far as the letters were concerned. The first stamp on the sheet bore A. B. in the upper corners, B. A. in the lower corners. The second stamp, A. C. in the upper, C. A. in the lower corners, etc. The second row bore B. A. in the upper, A. B. in the lower corners, etc. H. D. GRAHAM.--The line under the word "Postage" in the Hartford die of the centennial envelope is single. In the Philadelphia die it is double. All revenue stamps and stamped papers are collected by philatelists who make a specialty of this branch. U. S. Locals and Telegraphs are largely collected. I never saw a Postage Due U.S. in blue. I presume you have an essay of proof color. Did you take it off of a letter? W. T. FENNER.--The comparative worth of cancelled and uncancelled stamps varies, but as a rule the unused stamps are worth much more. In some instances, however, where large quantities were printed and only a few used, the proportion is the other way. A set of Postage Due U.S. of the current issue is worth face value only. F. A. R.--The 3c. blue U. S. is 1869 issue, worth 1c. used, 15c. unused. The green centennial envelope is worth 25c. R. BREHMER, 15 High Street, Rutland, Vt., wishes to exchange stamps, especially with foreign collectors. E. R. BEERE.--A Mexican dollar has more silver than an American dollar, but is worth only half as much. The 1806 half-cent is worth 15c. E. W. KEIFER.--The 1895 U.S. silver dollar is worth face only. The usual custom among numismatists is to obtain the fresh coins directly from the mint through a Philadelphia agent. E. HALL.--Never cut a pair or a strip of unperforated stamps. They are worth more together than singly.