The IET Archives holds a set of hand-written notes by Sir William Preece from 1877. These describe the mechanical and physical properties of Thomas Edison's newly invented 'speaking telegraph'.
In the IET Archives there are a fine set of hand-written notes by Sir William Preece, dated June 1 1877. These describe the mechanical and physical properties of Thomas Edison's newly invented 'speaking telegraph'. It was invented around the same time as Alexander Graham Bell's 'telephone' (1876), and the two inventions were hotly contested through the courts by their respective inventors, arguing as to who was the first to invent the telephone. Eventually, Bell's patent was accepted.
A third party, Elisha Gray, also claimed primacy, maintaining that despite his device being patented one hour after Bell's, his actually worked, whereas Bell's did not. Bell, of course, vehemently denied this claim! Amongst some historians, debate continues - and conflicting opinions still create a degree of confusion as to who actually invented the telephone. What is certain, though, is that the real conflict was between the inventors' egos!