Manchester Memoirs, Vol. Ixiii. (1920) A^^ 5 13 



of magnet cylinder, 1-5 tons. The magnet was wound with 13 wires of . 

 1/8 in. diameter in parallel. Total length of multiple cable 4.S00 feet. 

 Total weight of coils i-_? tons. \^'eight of magnet cylinder i-i tons. 

 Two armatures were provided, which were interchangeable: — 



(I.) "Intensity'' Armature, wound with 376 feet of 13 wires of |- in. diameter 

 in parallel. Total weight of wire, 232 lbs. Armature weight, 0-3 ton. 



(2.) " Quantity " armature, wound with 67 feet of copper plate, each 6 ins. 

 wide, 4 plates in parallel. Weight of copper, 344 lbs. Total weight of armature, 

 0-35 ton. 



The total weight of the dynamo was 45 tons. It was 80 ins. long, 2 feet 

 wide, and 5 feet high. 



Wilde tested his machines by the length of iron wire of stated thickness 

 that could be heated to redness or the thicknessi that could be melted. The 

 following values of voltages, current, and output have been deduced by Air. 

 A. Adamson for me from Wilde's experiments: — 



^ (a) 3 ins. of iron 0-04 in. diameter heated to redness. Machine at 2,500 

 revolutions per minute. 15 amperes, 1-7 volts, 25-5 watts. 



(B) 24 ins. of iron 0-04 in. diameter heated to redness. Excited by (A), 

 both 2,500 r.p.m. 15 amperes, 13-6 volts, 204 watts. Excited by 

 (A), both at 2,000 r.p.m. 8 ins. of wire of 0-04 in. melted. 30 

 amperes, total e.m.f. 20-5 volts. 



(C) 15 ins. of iron of 0-075 "i- nielted by estimated current of 64-7 

 amperes. 



(d) Armature at 1.500 r.p.m. No? i magneto with six magnets used to 

 excite (C), and the current 'from (C) excited (D). 

 Quantity armature: — 



15 ins. iron i/4in. melted; 390 amperes. 



15 ins. copper Vsi"- melted; 450 amperes. 

 Intensity armature: — 



21 ft. wire 0-065 in. heated to redness. 



29 amperes, 105 volts, 3,045 watts, 4-1 horse-power. 



7 feet iron 0065 in. melted; 52 amperes, 143 volts. 



Appendix C. 



List of the Chief Publicgtions of Henry Wilde. 



" On some new and paradoxical Phenomena in Electro-magnetic Induction, 

 and on a new and powerful Generator of Dynamic Electricity (The 

 Dynamo-electric j\Iachinc)." Rov. Soc, Proc, 1886. Pliil. Mag., 

 1867. Phil. Trans., 1867. 



" On the Electric Condition of the Terrestrial Globe, and on the Absolute 

 Character of the Law of Qelinite Electrolysis." Phil. Mag., 1868. 



" On a Property of the Magneto-electric Current to Control and render Syn- 

 chronous the Rotations of the Armatures of a number of Electro- 

 magnetic Induction (Dynamo) Machines."' Pliil. Mag., 1S69. 

 Memoirs,* vol. 30, 1887. 



" On the Influence of Gas- and Water-Pipes in determining the Direction 

 of a Discharge of Lightning." Phil. Mag., 1872. 



" On the Origin of Elementary Substances, and on some new Relations! of 

 their Atomic Weights. " Manchester Proc, \o\. i"]., 1878. Memoirs, \o\. y^, 



1878. • . . . 



" On some Improvements in Electro-magnetic (Dynamo) Machines." Phil. 

 Mag., vol. 45, June, 1873. 



" On the Velocity with which Air rushes into a \'acuum, and on some Phe- 

 nomena attending the Discharge of Atmospheres of Higher Densit\- 

 into Atmospheres of Lower Density. " Memoirs, \o\. y:), 1885. Phil. Mag., 

 1886. 



" On the Efflux of Air as modified by tlie Form of the Discharging Orifice." 

 Phil. Mag., 1SS6. Memoirs, vol. 30, 1886. 



