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business； and whose name； as Sir Josiah Mason； will ever be remembered for his munificent endowment of education。 It was agreed that I should not be judged by the novelty of my invention； but by the results which I promised； namely； of being able to deposit with a smooth surface 30 dwt。 of silver upon a dish…cover； the crystalline structure of the deposit having theretofore been a source of difficulty。 In this I succeeded； and I was able to return to my native country and my mechanical engineering a comparative Croesus。
'But it was not for long； as in the following year （1844） I again landed in the Thames with another invention； worked out also with my brother； namely； the chronometric governor； which； though less successful； commercially speaking； than the first； obtained for me the advantage of bringing me into contact with the engineering world； and of fixing me permanently in this country。 This invention was in course of time applied by Sir George Airy； the then Astronomer…Royal； for regulating the motion of his great transit and touch…recording instrument at the Royal Observatory； where it still continues to be employed。
'Another early subject of mine； the anastatic printing process； found favour with Faraday； 〃the great and the good；〃 who made it the subject of a Friday evening lecture at the Royal Institution。 These two circumstances； combined； obtained for me an entry into scientific circles； and helped to sustain me in difficulty； until； by dint of a certain determination to win； I was able to advance step by step up to this place of honour； situated within a gunshot of the scene of my earliest success in life； but separated from it by the time of a generation。 But notwithstanding the lapse of time； my heart still beats quick each time I come back to the scene of this； the determining incident of my life。'
The 'anastatic' process； described by Faraday in 1845； and partly due to Werner Siemens； was a method of reproducing printed matter by transferring the print from paper to plates of zinc。 Caustic baryta was applied to the printed sheet to convert the resinous ingredients of the ink into an insoluble soap； the stearine being precipitated with sulphuric acid。 The letters were then transferred to the zinc by pressure； so as to be printed from。 The process； though ingenious and of much interest at the time； has long ago been superseded by photographic methods。
Even at this time Siemens had several irons in the fire。 Besides the printing process and the chronometric governor； which operated by the differential movement between the engine and a chronometer； he was occupied with some minor improvements at Hoyle's Calico Printing Works。 He also engaged in railway works from time to time； and in 1846 he brought out a double cylinder air…pump； in which the two cylinders are so combined； that the compressing side of the first and larger cylinder communicated with the suction side of the second and smaller cylinder； and the limit of exhaustion was thereby much extended。 The invention was well received at the time； but is now almost forgotten。
Siemens had been trained as a mechanical engineer； and； although he became an eminent electrician in later life； his most important work at this early stage was non…electrical； indeed； the greatest achievement of his life was non…electrical； for we must regard the regenerative furnace as his MAGNUM OPUS。 Though in 1847 he published a paper in Liebig's ANNALEN DER CHEMIE on the 'Mercaptan of Selenium；' his mind was busy with the new ideas upon the nature of heat which were promulgated by Carnot； Clayperon； Joule； Clausius； Mayer； Thomson； and Rankine。 He discarded the older notions of heat as a substance； and accepted it as a form of energy。 Working on this new line of thought； which gave him an advantage over other inventors of his time； he made his first attempt to economise heat； by constructing； in 1847； at the factory of Mr。 John Hick； of Bolton； an engine of four horse…power； having a condenser provided with regenerators； and utilising superheated steam。 Two years later he continued his experiments at the works of Messrs。 Fox； Henderson； and Co。； of Smethwick； near Birmingham； who had taken the matter in hand。 The use of superheated steam was； however； attended with many practical difficulties； and the invention was not entirely successful； but it embraced the elements of success； and the Society of Arts； in 1850； acknowledged the value of the principle； by awarding Mr。 Siemens a gold medal for his regenerative condenser。 Various papers read before the Institution of Mechanical Engineers； the Institution of Civil Engineers； or appearing in DINGLER'S JOURNAL and the JOURNAL OF THE FRANKLIN INSTITUTE about this time； illustrate the workings of his mind upon the subject。 That read in 1853； before the Institution of Civil Engineers； 'On the Conversion of Heat into Mechanical Effect；' was the first of a long series of communications to that learned body； and gained for its author the Telford premium and medal。 In it he contended that a perfect engine would be one in which all the heat applied to the steam was used up in its expansion behind a working piston； leaving none to be sent into a condenser or the atmosphere； and that the best results in any actual engine would be attained by carrying expansion to the furthest possible limit； or； in practice； by the application of a regenerator。 Anxious to realise his theories further； he constructed a twenty horse…power engine on the regenerative plan； and exhibited it at the Paris Universal Exhibition of 1855； but； not realising his expectations； he substituted for it another of seven…horse power； made by M。 Farcot； of Paris； which was found to work with considerable economy。 The use of superheated steam； however； still proved a drawback； and the Siemens engine has not been extensively used。
On the other hand； the Siemens water…meter； which he introduced in 1851； has been very widely used； not only in this country； but abroad。 It acts equally well under all variations of pressure； and with a constant or an intermittent supply。
Meanwhile his brother Werner had been turning his attention to telegraphy； and the correspondence which never ceased between the brothers kept William acquainted with his doings。 In 1844； Werner； then an officer in the Prussian army； was appointed to a berth in the artillery workshops of Berlin； where he began to take an interest in the new art of telegraphy。 In 1845 Werner patented his dial and printing telegraph instruments； which came into use all over Germany； and introduced an automatic alarm on the same principle。 These inventions led to his being made； in 1846； a member of a commission in Berlin for the introduction of electric telegraphs instead of semaphores。 He advocated the use of gutta…percha； then a new material； for the insulation of underground wires； and in 1847 designed a screw…press for coating the wires with the gum rendered plastic by heat。 The following year he laid the first great underground telegraph line from Berlin to Frankfort…on…the…Main； and soon afterwards left the army to engage with Mr。 Halske in the management of a telegraph factory which they had