Guglielmo Marconi was born in Bologna, in Italy, in 1874. He became an electrical engineer and inventor and specialised in long distance radio transmission. He was awarded the Nobel Prize in Physics (jointly with Karl Ferdinand Braun) in 1909 for his contribution to the development of wireless telegraphy.

Marconi spent a number of years in Britain and in March 1897 he made some long distance wireless transmissions over areas of Salisbury Plain. Early in May of that year he travelled to South Wales and began experimenting on transmissions over the open sea from Flat Holm in the Bristol Channel to the cliff at Lavernock Point which is a mile or so south of Penarth, near Cardiff. Marconi’s assistant was George Kemp, a Post Office engineer from Cardiff. Kemp kept a diary of the events and this is his account of what happened in the second week of May, 1897:

Mr Marconi’s apparatus was set up on the cliff at Lavernock Point, which is about twenty yards above sea-level. Here we erected a pole, 30 yards (27 m) high, on the top of which was a cylindrical cap of zinc, 2 yards (1.8 m) long and 1-yard (0.91 m) diameter.Connected with this cap was an insulated copper wire leading to one side of the detector, the other side of which was connected to a wire led down the cliff and dipping into the sea. At Flat Holm Mr Preece’s apparatus was arranged, the Ruhmkorff coil also giving 20-inch (510 mm) sparks from an eight-cell battery.On the 10th May experiments on Mr Preece’s electro-magnetic transmission method were repeated, and with perfect success.

The next few days were eventful ones in the history of Mr Marconi. On the 11th and 12th his experiments were unsatisfactory — worse still, they were failures — and the fate of his new system trembled in the balance. An inspiration saved it. On the 13th May the apparatus was carried down to the beach at the foot of the cliff, and connected by another 20 yards (18 m) of wire to the pole above, thus making an aerial height of 50 yards (46 m) in all. Result, The instruments which for two days failed to record anything intelligible, now rang out the signals clear and unmistakable, and all by the addition of a few yards of wire!”

The first message transmitted (in Morse Code, of course) was, ‘Are you ready’, followed byCan you hear me’, to which the response came over, ‘Loud and clear’.

Photograph of Post Office Engineers with Marconi’s equipment (courtesy of Cardiff Council Flat Holm Project) :


There is a brass plaque set into the boundary wall of St Lawrence churchyard commemorating Marconi’s achievement:


Marconi died in Rome in 1937.