At the first step a German makes in one of the London streets, he must understand that life in England is very different from life in Germany. Not only are the walls of the houses black and smoky, but the houses do not stand on a level with the pavement. A London street is in a manner like a German high-road, which is skirted on either side with a deep ditch. In the streets of London the houses on either side rise out of deep side areas. These dry ditches are generally of the depth of from six to ten feet, and that part of the house, which with us would form the lower story, is here from ten to twelve feet underground. This moat is uncovered, but it is railed in, and the communication between the house door and the street is effected by a bridge neatly formed of masonry.
    Every English house has its fence, its iron stockade and its doorway bridge. To observe the additional fortifications which every Englishman invents for the greater security of his house is quite amusing. It is exactly as if Louis Napoleon was expected to effect a landing daily between luncheon and dinner, while every individual Englishman is prepared to defend his household gods to the last drop of porter.
    You may see iron railings, massive and high, like unto the columns which crushed the Philistines in their fall; each bar has its spear-head, and each spear-head is conscientiously kept in good and sharp condition. The little bridge which leads to the house-door is frequently shut up; a little door with sharp spikes protruding from it is prepared to hook the hand of a bold invader. And it is said, that magazines of powder are placed under the bridge for the purpose of blowing up a too pertinacious assailant. This latter rumour I give for what it is worth. It is the assertion of a Frenchman, whom the cleanliness of London drove to despair, and who, in the malice of his heart, got satirical.
    A mature consideration of the London houses shows, that the strength of the fortification is in exact proportion to the elegance and value of the house and its contents. The poor are satisfied with a wooden stockade; the rich are safe behind their iron chevaux de frise, and in front of palaces, club-houses, and other public buildings, the railings are so high and strong as to engender the belief that the thieves of England go about their business of housebreaking with scaling-ladders, pick-axes, guns, and other formidable implements of destruction.
    Every Englishman is a bit of a Vauban. Not only does he barricade his house against two-legged animals of his own species, but his mania for fortification extends to precautions against wretched dogs and cats. To prevent these small cattle from making their way through the railings, the Englishman fills the interstices with patent wire-net work, and the very roofs are frequently divided by means of similar contrivances. Vainly will cats, slaves of the tender passion, make prodigious efforts to squeeze themselves through those cruel, cruel walls, and vainly do they, in accents touching, but not harmonious, pour their grief into the silent ear of night. Vainly, I say, for an Englishman has little sympathy with "love in a garret" ; and as for love on the roof he scorns it utterly.
    We now approach the street-door, and put the knocker in motion. Do not fancy that this is an easy process. It is by far easier to learn the language of Englishmen than to learn the language of the knocker; and many strangers protest that a knocker is the most difficult of all musical instruments.
    It requires a good ear and a skilful hand to make yourself understood and to escape remarks and ridicule. Every class of society announces itself at the gate of the fortress by means of the rythm of the knocker. The postman gives two loud raps in quick succession; and for the visitor a gentle but peremptory tremolo is de rigueur. The master of the house gives a tremolo crescendo, and the servant who announces his master, turns the knocker into a battering-ram, and plies it with such goodwill that the house shakes to its foundations. Tradesmen, on the other hand, butchers, milkmen, bakers, and green grocers, are not allowed to touch the knockers-they ring a bell which communicates with the kitchen.
    All this is very easy in theory but very difficult in practice. Bold, and otherwise inexperienced, strangers believe that they assert their dignity, if they move the knockei' with conscious energy. Vain delusion! They arc mistaken -for footmen. Modest people, on the contrary, are treated as mendicants. The middle course, in this, as in other respects, is most difficult.

Max Schlesinger, Saunterings in and about London, 1853