3. Since the division of the metropolis into postal districts, those requiring frequent communication with different parts of London will find of great service a penny book which contains a list of all the streets, &c. in London and its environs, as divided into the ten districts, and giving the initials in each case. This book may be purchased at any post-office. It is said that delay is sometimes avoided by adding the initials of the London districts to letters forwarded from the provinces. 4. As a rule, with few exceptions indeed, letters are forwarded according to their address. It is of paramount importance, therefore, that the addresses of letters should not only be legible, but the proper and the complete address. Perhaps the following suggestions on this head may be found useful, viz.:-- (_a_) Never to post a letter without addressing it either a post town or a county. If the information cannot otherwise be obtained, the "British Postal Guide" contains a list of all post-offices in the United Kingdom, and gives post town to which they are subordinate. (_b_) Letters for small towns or villages ought not to addressed to the nearest large town, merely because it the _nearest_; although, as a rule, the town in question will be the correct post town, there are many exceptions, which can only be known by reference to the "Guide" provided, or by inquiry. (_c_) If the town be not well known, or if there be two towns of the same name in the country, the _county_ ought to be added. (All the cities and county towns are well known.) Thus, letters addressed to Newport should always give the county, inasmuch as there are several towns and villages of that name in England. Again, letters for Newcastle should either have the county added, or the usual designation thus: Newcastle-on-Tyne, Newcastle-under-Lyme, or Newcastle Emlyn. (_d_) Letters posted in England for Scotland or Ireland, _vice versâ_ (except in the case of the great towns of the three countries), should have the name of the country to which they are sent given as part of the address. N. B. (North Britain) for Scotland, and S. B. (South Britain) for England, would generally be thought sufficient for letters circulating between the two countries. (_e_) Foreign letters should invariably have the name of the country given (in English if possible). It ought also to be given in full. Letters addressed "London, C. W." and intended for London in Western Canada, have not unfrequently been sent to the West Central District in London, and so delayed. Letters addressed to "Hamilton, C. W." have also been mis-sent to Hamilton in Scotland, the initials having been overlooked.