During December we will post more packages, make more phone calls, send more text messages and possibly even meet more people face to face than in any other month. What most of us will not be doing is communicating by telegraph, which was one of the most dramatic communication technologies in terms of its impact. By allowing for much speedier communication, it played a big role in making the globe feel smaller. What you may not know is that Ireland played an important role in its history.
An early version of the electric telegraph (Cooke and Wheatstone’s 1837 model) was first used in England for railway signalling. The potential of the technology to enhance communication and to speed the relay of messages across the growing British empire had long been recognised. In fact, as Adrian Kirwan explained at the recent HSTM Network Ireland conference, optical versions had still been in development at the start of the 19th century. Richard Edgeworth was trying to sell a system of enormous spinning pointers placed atop towers on high ground to a British government that was wary of a potential French invasion. By the mid-19th century, optical telegraphs had been replaced by electrical ones.
The innovation that dramatically extended the reach of the telegraph was the submarine cable. The first submarine cable in Britain and Ireland was laid across the English Channel in 1851. Soon government, scientists and entrepreneurs had their sights set on a cable linking Europe and North America. The island of Valentia, off the coast of Kerry, was chosen as the European end, although there was an abortive bid by geologist William King to have it moved to Galway. The first attempt to lay the cable, in 1856-1858, ended in failure when the cable worked erratically and then went completely quiet.
A successful long-distance submarine cable was fraught with difficulty. Simply trying to lay the cable had been an arduous process involving about 2,500 miles of heavy, breakable cable. Before laying began, scientists had debated what the cable should be like to achieve speed and accuracy of signal transmission. Arguments centred on the ideal thickness of the cable itself.
The Atlantic Telegraph Company had, in 1856, taken the surgeon Edward Whitehouse as a scientific adviser. Whitehouse had an interest in the emerging science of electricity and had conducted extensive telegraph experiments. He claimed that signal retardation (or slowing) did not necessarily increase with the increased length of the cable. By contrast, the Irish-born engineer William Thomson argued that a longer cable must always reduce retardation. Unfortunately for Whitehouse's career, Thomson was proved correct. Whitehouse was fired and Thomson took his place.
Thomson had to work hard to encourage enthusiasm for a second attempt at laying the cable. The 1856-1858 cable “leaked” signal from insulation and thus Whitehouse applied high levels of current to compensate. This probably ruined the already weak cable. The project had been an expensive and embarrassing failure, and some thought the only solution was an overland cable laid via Russia, with a much shorter submarine portion linking Siberia to North America.
Thomson in effect resolved the problem by focusing on developing more sensitive instruments to receive weak signals, notably the mirror galvanometer. This could turn even a very weak electrical current into a signal by replacing the mechanical pointer with a deflected beam of light. The first new cable, laid in 1865, failed, but the one laid in 1866 was a success that lasted many years. Valentia telegraph station assumed an important place in global communication and Thomson was knighted in 1867.
When I picked up the phone as a child I imagined a connection not unlike a tin can telephone with a wire running between callers. Of course, even the telegraph was never that simple, but when you talk to loved ones across the world over this holiday season, think back and thank those early telegraph enthusiasts for having the vision to imagine that the world could really be connected by wires.
- Juliana Adelman lectures in history at St Patrick's College Drumcondra
