The post office and its story an interesting account of the activities of a great government department

The large central hall facing the main entrance to the building is set apart for the circulation of telegrams received from the various branch offices connected with the Central Office by pneumatic tube, and in the reverse directions for delivery from these offices. A large staff of telegraphists is engaged upon this work. The pneumatic tubes used for forwarding and receiving telegrams to and from certain branch offices in the city, western central, and western district offices, and so obviating telegraphic transmissions, are led into this hall. These tubes are laid at the depth of about two feet underground. They extend as far distant as Billingsgate on the eastern side, House of Commons and West Strand on the south-western side, and the western district office on the western side, and allow of the rapid collection and distribution of telegrams over a very busy area. The tubes make the various offices arms practically of the Central Station so far as telegrams are concerned. The message forms are enclosed in gutta-percha carriers covered with felt, and having attached to their forward ends a number of felt discs which exactly fit the internal circumference of the tubes and prevent any escape of air around them. An elastic band at the mouth of the carrier prevents the messages from escaping. The outgoing carriers containing the messages are propelled through the tubes from the Central Office by forcing compressed air into the tubes behind them at a pressure of about 10 lbs. to the square inch, the incoming carriers being drawn through by vacuum, so that the normal atmosphere exerts behind them a pressure of about 7 lbs. to the square inch.