It is nearly six o'clock now, and opposite is the large building of the Post-Office where the letters are dealt with. Up the steps in front we see the huge letter-box, with a great gaping slit of a mouth into which boys and men are pouring letters as fast as they can; for at six o'clock the country letters are sent off, and any posted after that will not be delivered first thing next morning in the country, but will arrive later.
Come inside; we have a special order so that we can be admitted without any difficulty. Now we see from the inside what we saw from the outside a minute ago. It is like looking at the inside of a piece of machinery. We see now only the big slit and the eager hands thrusting letters into it, more letters and more, which fly down inside like a snowstorm of enormous flakes. They drop into great clothes baskets, which are filled up every minute, and when full are dragged away by the postmen inside, who thrust others into their places, others which, incredibly quickly, are filled up, too, and dragged away. Rattle, rattle; down come the letters. One boy outside has a bag, which he empties by tipping it up so that a stream of letters runs down; he must be from an office. Here is another, and another; but at last six o'clock strikes, the great baskets have been dragged away, and no more letters for the country go until much later. The basketfuls have been emptied into sacks; these sacks are tied up with string and sealed with a piece of sealing-wax a good deal thicker than your wrist, and then they are flung down into the bright scarlet carts, which belong to the Post-Office, and which stand waiting outside. Each driver starts off punctually with his load, and drives to another great office in London where the country letters are sorted out and sent off. All this business used to be done here where we are, but in the last year or two it has been found better to keep the London and the country letters separate.
Now we turn to look at the London ones. There is a separate box for them to be posted in. Perhaps you who live in the country have never seen that. At every large London office there are two boxes side by side, and into one the people put their letters meant for the country, and into the other those for London. The London letters are gathered from the box and thrown out upon large tables, and down each side a row of boys and men stand and sort them out like a pack of cards, putting them all together, face up, and with the stamp in the same position. When they are arranged the boys carry a great bundle to another man who has to stamp them, so as to mark the stamp in case it should be used again. There is a very clever contrivance for this. A little round wheel spins at a tremendous pace, and on it are dark lines covered with wet ink. A man holds the letters and pushes them one by one up to the wheel, which, when it touches them, drags them through a narrow space in front, and as they pass the wheel the ink-lines run across the stamp and mark it so that it cannot be used again. So quickly does the little wheel whirr and the letters spin past that five hundred are done in a minute. Think of that; it means nearly nine a second. Nine letters stamped while you say 'One--two,' which is a second. Some letters are too thick and others too big to go through the little space by the wheel, so the man who is looking after them picks out those and throws them up on to a tray, from which they are gathered up and carried to another man, who stamps each by hand, a much slower process.