Bankers Weather Station: Arne Jacobsen's Ø12 Instruments as a Set

Arne Jacobsen drew the Bankers clock for a central bank, and the same face now reads air pressure, humidity and temperature as well as the time. This piece looks at the three Ø12 cm weather instruments in the Bankers family, how they sit beside the matching wall clock, and which of them earns its place on your wall.

From a bank wall to a weather station

Danmarks Nationalbank in Copenhagen is one of Jacobsen's late, severe buildings: long stone facades, a vast lobby and an interior he controlled down to the fittings. For it he designed a wall clock with a plain white face, slim black indices and no numerals, the kind of dial that tells the time at a glance across a large room and then gets out of the way. That clock became known simply as Bankers.

The weather station takes the Bankers clock as its starting point. Rather than inventing a new object for each reading, the series keeps one case, one diameter and one graphic language, and changes only what the dial measures. There are four pieces in all: a clock for the time, a barometer for air pressure, a hygrometer for relative humidity and a thermometer for temperature. Each measures Ø12 cm, and each comes in the same white, black and red colourway.

Jacobsen worked this way throughout his career. At the SAS Royal Hotel he designed the building, the chairs, the lamps and the cutlery as one system, and the Bankers instruments follow the same thinking at a much smaller scale: once the form is right, repeat it and let the content change.

Three instruments, one face

The three weather pieces share almost everything with the clock. The case is aluminium, the front is a mineral glass lens, and the inner parts are ABS. All four weigh 0.26 kg. The only measurable difference between them is depth.

• Barometer: Ø12 cm, 4.5 cm deep, 0.26 kg. The Bankers Barometer Ø12 cm white/black/red shows air pressure, the reading that has long been used to anticipate a change in the weather. It is the one piece that sits a little further off the wall.
• Hygrometer: Ø12 cm, 4 cm deep, 0.26 kg. The Bankers Hygrometer Ø12 cm white/black/red shows relative humidity, the share of moisture in the air compared with what it could hold at that temperature.
• Thermometer: Ø12 cm, 4 cm deep, 0.26 kg. The Bankers Thermometer Ø12 cm white/black/red shows room temperature on the same clean scale.
• Wall clock: Ø12 cm, 4 cm deep, 0.26 kg. The Bankers Wall clock Ø12 cm white/black/red completes the set and runs on a battery-operated movement.

That half centimetre on the barometer is worth knowing if you plan to hang the pieces tight together on a narrow wall, but in a row at eye level it is barely noticeable. What you see is four identical white discs with black graphics and one red hand each.

The red hand and the logic of the dial

On a dial with no numerals and very little ink, colour does the work. The faces are white, the scales and markings are black, and red is kept for a single hand. On the clock that red line is the moving one your eye follows; on the weather instruments the red pointer is the reading itself. Because red appears once per dial, you can read any of the four from across the room without searching the face.

This restraint is why the set looks calm on a wall even when four instruments hang side by side. There are no competing colours, no decorative bezels and no brand marks fighting for space. Hung together, the four red hands become a small rhythm of their own, each pointing somewhere different, which gives the group a quiet sense of life.

The mineral glass lens sits flat over the dial, so the faces stay crisp under side light from a window. Care is simple: wipe the glass and case with a dry, soft cloth, and avoid sprays that could creep under the edge of the lens.

Where a hygrometer is genuinely useful

A barometer is the romantic choice and a thermometer is the familiar one, but in a modern home the hygrometer is often the instrument you will actually consult. Relative humidity affects comfort, materials and health in ways that a room thermostat does not show you.

• Living rooms with wooden furniture and floors. Solid wood takes on and gives off moisture with the seasons. Very dry winter air from radiators or underfloor heating can open joints and cause cracks, while persistently damp air can make drawers stick. A hygrometer tells you when to air the room or run a humidifier.
• Rooms with instruments. Pianos, guitars and violins are sensitive to humidity swings. Musicians often keep a hygrometer near the instrument for exactly this reason.
• Bedrooms. Dry air in winter can leave your throat and skin uncomfortable overnight, and too much moisture encourages condensation on cold windows. A reading by the bed helps you decide whether to open a window or leave it closed.
• Hallways and rooms near a bathroom. Damp from showers travels. A hygrometer in a hallway shows whether ventilation is clearing it or whether moisture lingers, which is an early warning for mould on cold outer walls.
• Rooms full of plants or books. Tropical houseplants prefer more moisture than most heated homes provide, while paper and bindings prefer stable, moderate conditions.

Treat the dial as a guide to trends rather than a laboratory reading. Watching the red pointer move after you air a room, cook or dry laundry indoors teaches you more about your home than any single number.

Hanging the set as a row

Because all four pieces are the same diameter, the classic arrangement is a straight horizontal row. Keep the gaps equal, and choose a gap that relates to the 12 cm discs: a few centimetres reads as one object, a wider spacing reads as a measured line of instruments. Mark the centre line in pencil first, and hang the pieces with their centres on it rather than their tops, so the deeper barometer does not throw the alignment.

The natural order is the order of the series itself: clock, barometer, hygrometer, thermometer, or with the clock at one end so the eye starts with the time. A row works well above a desk, along a hallway, over a sideboard or beside a front door, where you glance at the weather before heading out. For a tall narrow wall, a vertical column has the same effect.

You do not need all four. A pair of clock and hygrometer is the most useful duo for a bedroom or study. Three pieces without the clock suit a kitchen or entrance that already has a clock elsewhere. Even a single instrument looks complete on its own, which is the advantage of a face designed to stand alone on a bank wall.

If you already own a larger Bankers clock, the Ø12 cm instruments can sit beside it as a smaller satellite group. Our guide to Arne Jacobsen wall clocks: Bankers, Roman, Station and City Hall sets out how the different dials compare. To see the weather station alongside other wall and table clocks, browse the Clocks collection.