The Great Exhibition opened in London 150 years ago today. On May 1st, 1851, half a million people thronged into Hyde Park for the event, but only a fraction of them would have heard the Prince Consort describe it as "a true test and a living picture of the point of development that mankind has reached, and a new starting point from which all nations will be able to direct their further exertions".
The exhibition epitomised the new self-confident, almost arrogant optimism of Victorian Britain. It was housed in the magnificent Crystal Palace, a giant hall of glass covering 19 acres and more than a million square feet of floor space.
There, under a single roof, could be found machinery, manufactured goods and works of art from all over the world, exemplifying man's expanding industry and limitless ambition.
The aim was to "seize the living scroll of human progress, inscribed with every successive conquest of man's intellect".
One conquest of man's intellect that was duly celebrated at the exhibition was a new development in meteorology. Until the middle of the 19th century, without rapid communications, weather forecasting in any meaningful sense seemed impossible.
It is only by analysing the existing patterns of temperature and pressure over a wide area that the forecaster can identify weather systems and predict their arrival. If the information takes too long to come, the forecasts will be "history" before they are prepared. This was the dilemma facing early meteorologists.
But then Samuel Finley Breese Morse, an American, devised the electric telegraph, and a clever code of dots and dashes which allowed messages to be transmitted. The US Congress gave Morse money which was used to build an experimental line from Washington to Baltimore.
It was along this line in 1844 that Morse used his code to send the first telegraphic message - a quotation from Chapter 23 of the Book of Numbers: "What hath God wrought".
What indeed! Meteorology had acquired a tool which was to revolutionise the science in just a few decades.
During the next few years telegraph networks were installed in many countries. By 1851, the telegraph had made the construction of a daily weather chart "in near real time", as we nowadays would say, a possibility.
And thus it was that at the Great Exhibition a current weather map for the island of Britain was prepared daily for the first time, with litho graphed copies being sold to the public at one penny each.