There are four cardinal marks and they indicate the direction of safe water if there is a hazardous area nearby. They are called Cardinals because there is one for each of the cardinal points of a compass. North, South, East and West. Take a look at the diagram below:
Starting at the top of the diagram then, a north cardinal is saying, “Stay north of me, the danger is to the south”. It has two upward pointing cones as a top mark. Pointing to the top of the compass, which is north.
Let’s move clockwise to the east cardinal. This is saying, “Stay east of me, the danger is to the west”. The top mark has two cones pointing away from each other. To help you remember this, the cones look like an Easter Egg!
Next, the south cardinal is saying, “Stay south of me, the danger is to the north”. As it’s opposite to the north cardinal and at the bottom of the compass, it has two downward pointing cones as a top mark.
Finally the west cardinal is saying, “Stay west of me, the danger is to the east”. The top mark has two cones pointing towards each other. To help you remember this, the top mark looks like a Waist or a Wine glass. Both of which start with a ‘W’ for west.
Regarding the colours of the cardinal marks, they are obviously all black and yellow. Closer attention will show you that the top mark cones indicate where the black areas will be.
North Cardinal – two upward pointing cones – black top half
East Cardinal – one up, one down – black at the top and bottom with a yellow band in the middle (an Easter Egg has a yellow ribbon)
South Cardinal – two downward pointing cones – black bottom half
West Cardinal – two inward pointing cones – black band in the middle
An important note about cardinal marks in real life is that you won’t necessarily see all four around a hazard. For example, a single south cardinal could be telling to stay south of a rocky shore.
A North Cardinal has a continuous flashing white light. This light is either quick or very quick. It would be shown on a chart as either Q or VQ.
An East Cardinal displays three white flashes. These are either quick or very quick. The lights will be displayed in either a 5 second or a 10 second time period depending on their speed. The ways this would be depicted on a chart are:
A South Cardinal shows 6 white flashes followed by a long white flash. These can again be quick or very quick. They will be in either a 10 second or 15 second time period respectively.
The reason they have a long flash after the 6 white flashes is to prevent it being easily confused with any other light.
The ways in which the light will be depicted on a chart are either:
Finally a West Cardinal displays 9 white flashes. These are again quick or very quick and they are in either a 10 or 15 second time period.