It is always well to remember, that for any given delivery, a letter may be posted rather later at the chief office than at any of the minor offices of each district; that _letters_ only, not newspapers, book-parcels, manuscripts, &c., may be put in pillar-boxes; and that letters posted during the night, (from 9 p.m. to 5 a.m.,) have a chance of earlier delivery than otherwise, seeing that the pillar-boxes are cleared at 5 in the morning, and, as a rule, we believe, earlier than the receiving-houses. Outgoing letters for the evening mails are received at most offices till 5.30, and at the chief office of each district till 6. By affixing an extra penny stamp, the letter is receivable till 6 at the minor, and till 7 at the chief offices. Telegraph Offices.—Telegrams may be sent from all Postal Offices within the London district. The charge for 20 words, not including address, is 1s. READING AND NEWS-ROOMS. Jerusalem Coffee-house, Cowper’s Court, Cornhill, (Indian, China, and Australian newspapers.) 3 Wallbrook. 154 Leadenhall Street, (Deacon’s.) 13 Philpot Lane. Royal Exchange, Lloyds’, (Subscribers only.) King’s Head, Fenchurch Street. 26 Fore Street, Cripplegate. 88 Park Street, Camden Town. 83 Lower Thames Street. 177, 178 Fleet Street, (Peele’s—files of the _Times_ for many years.) 24 King William Street, (Wild’s.) 34 Mount Street, Grosvenor Square, (St. George’s.) 22 Paddington Green, (Working Men’s.) Patent Museum Library, Southampton Buildings, Chancery Lane, (free.) British Museum Library, (apply for ticket; enclosing letter of introduction from respectable householder.) * * * * * There are Reading and News Rooms belonging to a large number of learned societies and public institutions; but these are for the most part accessible only to members. CHESS ROOMS. A chess player may meet with competitors at any one of the several chess rooms. The best are Simpson’s, (Limited Co.,) late Ries’s, _Divan_, opposite Exeter Hall, Strand; Kilpack’s, Covent Garden, (also an American Bowling Saloon;) and Pursell’s, Cornhill. Many Coffee-shops are provided with chess-boards and men, and many dining and chop houses have chess-rooms up-stairs. THEATRES. There are at present about thirty-seven London Theatres, but those named below are all that need here be considered.