12 Haldane Gee — Hairy //7A/c 



Conclusion. 



Henry Wilde' s many inventions establish his position as a 

 pioneer in Electrical Engineering; but it is not easy to give a 

 just estimation of his scientific work. It must be remembered that 

 he was a self-educated man. He was a great student of the 

 earlier writers on science and philosophy, and his papers are full 

 of quotations from them. He never realised the great advances 

 that were being made in electrical science and the application of 

 the laws of energy. Had his mental disposition been such as to 

 tolerate guidance, his later work would have been of greater 

 value, and he would have been saved from regarding as parado.xes 

 experimental facts that could easily be explained. Although he 

 cannot rank with Dalton and Joule^ yet in the history of the affairs 

 of the Society he held a unique position, and his benevolence 

 at a critical time must ever be remembered. 



Henry Wilde married Miss Lowe, the sister of his partner. 

 She died about eighteen years ago, and there were no children. 

 Henry died on March 28th, 191 9, at the age of eighty-six, at 

 The Hurst, Alderley Edge. He and his wife are buried at 

 Bunbury in Cheshire. 



Appendix A. 

 Galvajionieter zised by Wilde. 



The tangent and sine galvanometer used by Wilde in his experiments with 

 his magnetos, whirh is in the possession of the Society, is a fine instrument of 

 brass as des,igned by Pouillet. It was made by Ruhmkorfi of Paris. It has a 

 compass box of 6^ ins. diameter and a brass hoop 125 ins. in diameter. 

 As a sine galvanometer, its readings can be taken to 2 minutes by a vernier; 

 as a tangent galvanometer, tenths of a degree can be estimated. There are 

 two coils, each of 0-15 ohm. When in series, the constant as a tangent 

 instruments in the field of the earth has been determined for me by Dr. A. 

 Fergusoii to be about 0-13. Assuming (hat Wilde used the two coils in series, 

 the maximum current obtained from his magneto when the lour magnets were 

 in jilace was only about oiie-lillh of an ampere. 



' Appendix B. 



Details of Wilde's Early Machines. 



{A) Magneto-Electric Machine {No 2). Bore of cylinder, i\ ins.; length; 

 12 ins. Armature wound with 67 feet of insulated wire 0-15 in. diameter. 

 This gives an armature resistance of about o"027 ohm. The field con- 

 sisted of 16 magnets 12 ins. long, each 3 lbs. in weight and capable of 

 supporting 20 lbs. 



(B) Electro-Magnetic Mar/iinc (Xo. 1). Bore and length of magnet cylin- 

 der as in (a). Magnet limbs of boiler plate i2iX9X3/8in. Wound 

 with 700 feet of insulated copper wire 0-15 in. diameter. (R=o-28 

 ohm.). 



<{C) Electro-Magnetic Machine (jXo. 2). Bore and length of magnet cylin- 

 der double that of (B), namely 5 ins. and 25 ins. respectively. Magnet 

 wound with 1,170 feet of wire weighing 390 lbs. .\rmature with 84 feet 

 of wire weighing 28 lbs. 



(D) ElectrO'Magnctir Machine (No. j). Dimensions of bore and length of 

 magnet cylinder double those of (C). Each limb of the electro-magnet 

 was of rolled iron 48 X 39 X li '"s. Weight of electro-magnet exclusive 



