Plate from 'The Weather Book' by Admiral Robert Fitzroy (1805-1865). The coloured illustration shows the mixing of cold polar air with warm tropical air currents, over Britain and the North Sea. The blue crayon represents cold air and the red, warm air. Fitzroy was an English naval officer and meteorologist, who captained the 'Beagle' during Darwin's voyages. He was later made the first head of what was to become the Meteorological Office and introduced the first published daily weather forecasts in The Times in 1860. Fitzroy also devised a system of signals appropriate for use by day or night which would be hoisted above a harbour to warn shipping of imminent storms, effectively the precursor of the modern shipping forecast broadcast on the radio.
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