In an earlier article I argued that much of what used to be called “modern physics” stems from the intersection of two earlier technologies: high vacuum and high voltage. In this article I will discuss the induction coil, invented in the 1830s, reinvented in the second half of the 19th century, and still used today to produce the high voltages used to excite gaseous and high-vacuum discharge tubes.

1.
Thomas B.
Greenslade
Jr.
, “
Physics stories
,”
Phys. Teach.
56
,
286
289
(
May
2018
).
2.
Sidney G.
Starling
,
Electricity and Magnetism for Advanced Students
, 2nd ed. (
Longmans, Green and Co.
,
London
,
1916
), p.
319
3.
Henry M.
Noad
,
The Student’s Textbook of Electricity
, revised by W. H. Preece (
Crosby Lookwood and Co
,
London
,
1879
), p.
361
.
4.
E. Taylor
Jones
,
The Induction Coil – Theory and Applications.
This book, published in 1932 and reprinted in 2008, is available online and will satisfy those who wish to see a more complete theory of the induction coil.
5.
Thomas B.
Greenslade
Jr.
, “
Apparatus named after our academic ancestors – I
,”
Phys. Teach.
48
,
604
606
(
Dec
.
2010
). This reference has a picture of a Ruhmkorff coil made in England in 1869.
6.
Thomas B.
Greenslade
Jr.
, “
Devices to display electromagnetic rotation
,”
Phys. Teach.
34
,
412
416
(
Oct.
1996
).
7.
Daniel
Davis
Jr.
,
Davis’s Manual of Magnetism
(
Daniel Davis Jr.
,
Boston
,
1842
)
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