James Wimshwst. 301 



several modifications of a practical kind ; but, not being satisfied with 

 any of them, he designed the type of instrument associated with his 

 name, having two circular plates rotating in opposite directions, and 

 having metallic sectors on the outer faces of each. Later, he devised 

 very powerful multiple-plate machines on the same plan, with many 

 original details. He constructed with his own hands more than ninety 

 influence machines, large and small, many of which he presented to his 

 scientific friends. He constructed the gigantic two-plate machine for 

 the Science Collection at South Kensington. Others had cylindrical 

 plates, and one was designed with two ribbons, which travelled past 

 one another in opposite directions. He took no patents for his 

 improvements, a circumstance which he regretted later, not on account 

 of any pecuniary reward that he had sacrificed, but because, in the 

 absence of any patent-rights, he could not exercise any control over 

 the design or construction of inferior machines which were put upon 

 the market in his name. In 1896, when Eontgen made the discovery 

 of the rays emanating from highly-exhausted Crookes' tubes, Wimshurst 

 found his influence machine to be an admirable means of exciting them, 

 and he showed that for screen observation, where a steady illumination 

 is desirable, the steady discharge from one of his eight-plate influence 

 machines was preferable to the intermittent discharge of the usual 

 induction coil. He became exceedingly interested in this application 

 of his machines and in their application in hospitals to produce high- 

 tension discharges for the treatment of lupus and other skin diseases. 

 He was an active Member of the E-ontgen Society, to which, as well 

 as to the Physical Society, he communicated several papers. In 1889 

 he was elected a Member of the Institution of Electrical Engineers, 

 and belonged to various other learned and professional Societies. He 

 was elected a Fellow of the Royal Society in 1898. Exceedingly simple 

 in his own personal tastes and manner of life, he was sincerely generous 

 and hospitable, always willing to aid younger men in any scientific 

 work, and never better pleased than when he could gather a few of 

 his friends around him in his laboratory to spend an evening upon 

 experiments, old and new. He died of heart disease on January 3, 1903. 



S. P. T. 



