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ersons transplanted pieces of their flesh into each other； and tattooed the grafts with letters； a sympathetic telegraph could be established by pricking the letters。＇
Dr。 Gilbert； physician to Queen Elizabeth； by his systematic researches； discovered the magnetism of the earth； and laid the foundations of the modern science of electricity and magnetism。 Otto von Guericke； burgomaster of Magdeburg； invented the electrical machine for generating large quantities of the electric fire。 Stephen Gray； a pensioner of the Charterhouse； conveyed the fire to a distance along a line of pack thread； and showed that some bodies conducted electricity； while others insulated it。 Dufay proved that there were two qualities of electricity； now called positive and negative； and that each kind repelled the like； but attracted the unlike。 Von Kleist； a cathedral dean of Kamm； in Pomerania； or at all events Cuneus； a burgher； and Muschenbroek； a professor of Leyden； discovered the Leyden jar for holding a charge of electricity； and Franklin demonstrated the identity of electricity and lightning。
The charge from a Leyden jar was frequently sent through a chain of persons clasping hands； or a length of wire with the earth as part of the circuit。 This experiment was made by Joseph Franz； of Vienna； in 1746； and Dr。 Watson； of London； in 1747； while Franklin ignited spirits by a spark which had been sent across the Schuylkill river by the same means。 But none of these men seem to have grasped the idea of employing the fleet fire as a telegraph。
The first suggestion of an electric telegraph on record is that published by one 'C。 M。' in the Scots Magazine for February 17； 1753。 The device consisted in running a number of insulated wires between two places； one for each letter of the alphabet。 The wires were to be charged with electricity from a machine one at a time； according to the letter it represented。 At its far end the charged wire was to attract a disc of paper marked with the corresponding letter； and so the message would be spelt。 'C。 M。' also suggested the first acoustic telegraph； for he proposed to have a set of bells instead of the letters； each of a different tone； and to be struck by the spark from its charged wire。
The identity of 'C。 M。；' who dated his letter from Renfrew； has not been established beyond a doubt。 There is a tradition of a clever man living in Renfrew at that time； and afterwards in Paisley； who could 'licht a room wi' coal reek （smoke）； and mak' lichtnin' speak and write upon the wa'。' By some he was thought to be a certain Charles Marshall； from Aberdeen； but it seems likelier that he was a Charles Morrison； of Greenock； who was trained as a surgeon； and became connected with the tobacco trade of Glasgow。 In Renfrew he was regarded as a kind of wizard； and he is said to have emigrated to Virginia； where he died。
In the latter half of the eighteenth century； many other suggestions of telegraphs based on the known properties of the electric fire were published； for example； by Joseph Bozolus； a Jesuit lecturer of Rome； in 1767； by Odier； a Geneva physicist； in 1773； who states in a letter to a lady； that he conceived the idea on hearing a casual remark； while dining at Sir John Pringle's； with Franklin； Priestley； and other great geniuses。 'I shall amuse you； perhaps； in telling you；' he says；'that I have in my head certain experiments by which to enter into conversation with the Emperor of Mogol or of China； the English； the French； or any other people of Europe 。。。 You may intercommunicate all that you wish at a distance of four or five thousands leagues in less than half an hour。 Will that suffice you for glory？'
George Louis Lesage； in 1782； proposed a plan similar to 'C。 M。's；' using underground wires。 An anonymous correspondent of the JOURNAL DE PARIS for May 30； 1782； suggested an alarm bell to call attention to the message。 Lomond； of Paris； devised a telegraph with only one wire； the signals to be read by the peculiar movements of an attracted pith…ball； and Arthur Young witnessed his plan in action； as recorded in his diary。 M。 Chappe； the inventor of the semaphore； tried about the year 1790 to introduce a synchronous electric telegraph； and failed。
Don Francisco Salva y Campillo； of Barcelona； in 1795； proposed to make a telegraph between Barcelona and Mataro； either overhead or underground； and he remarks of the wires； 'at the bottom of the sea their bed would be ready made； and it would be an extraordinary casualty that should disturb them。' In Salva's telegraph； the signals were to be made by illuminating letters of tinfoil with the spark。 Volta's great invention of the pile in 1800 furnished a new source of electricity； better adapted for the telegraph； and Salva was apparently the first to recognise this； for； in the same year； he proposed to use it and interpret the signals by the twitching of a frog's limb； or the decomposition of water。
In 1802； Jean Alexandre； a reputed natural son of Jean Jacques Rousseau； brought out a TELEGRAPHE INTIME； or secret telegraph； which appears to have been a step…by…step apparatus。 The inventor concealed its mode of working； but it was believed to be electrical； and there was a needle which stopped at various points on a dial。 Alexandre stated that he had found out a strange matter or power which was； perhaps generally diffused； and formed in some sort the soul of the universe。 He endeavoured to bring his invention under the eye of the First Consul； but Napoleon referred the matter to Delambre； and would not see it。 Alexandre was born at Paris； and served as a carver and gilder at Poictiers； then sang in the churches till the Revolution suppressed this means of livelihood。 He rose to influence as a Commissary…general； then retired from the army and became an inventor。 His name is associated with a method of steering balloons； and a filter for supplying Bordeaux with water from the Garonne。 But neither of these plans appear to have been put in practice； and he died at Angouleme； leaving his widow in extreme poverty。
Sommering； a distinguished Prussian anatomist； in 1809 brought out a telegraph worked by a voltaic battery； and making signals by decomposing water。 Two years later it was greatly simplified by Schweigger； of Halle； and there is reason to believe that but for the discovery of electro…magnetism by Oersted； in 1824 the chemical telegraph would have come into practical use。
In 1806； Ralph Wedgwood submitted a telegraph based on frictional electricity to the Admiralty； but was told that the semaphore was sufficient for the country。 In a pamphlet he suggested the establishment of a telegraph system with public offices in different centres。 Francis Ronalds； in 1816； brought a similar telegraph of his invention to the notice of the Admiralty； and was politely informed that 'telegraphs of any kind are now wholly unnecessary。'
In 1826…7； Harrison Gray Dyar； of New York； devised a telegraph in which the spark was made to stain the signals on moist litmus paper by decomposing nitric acid； but he had to abandon his experiments in Long Island and fly the country； because of a writ which charged him with a conspiracy for