26

Bioelectromagnetism

generated with the emission of both sound and light. When rubbed by a cloth pressed against it by the

hand, Guericke heard for the frst time sound and saw for the frst time light in artifcially exited elec­

tricity (Mottelay, 1922). In addition, he was historically a well-famed scientist for his research on the

nature of vacuum (Magdeburg Hemispheres). Te Middlesex Hospital (England) was probably the frst

hospital to purchase an electric machine in 1767 (Cambridge, 1977).

Renē Descartes (1595–1650), the French physicist, mathematician, and philosopher, theorized that

the magnetic poles were on the central axis of a spinning vortex of fuids surrounding each magnet. Te

fuids entered by one pole and lef through the other. Sir Isaac Newton (1642–1727) improved the electric

machine by substituting with a glass globe the globe of sulfur used for the electric machines of both

von Guericke and Robert Boyle (1627–1691), an Irish natural philosopher and chemist. In his work book

“Optiksi,” Newton had posited the existence of a single universal ether which would explain everything

from light, heat, and gravity through electricity and magnetism to nervous impulses and vision (Tatar,

1978). Ether is, according to Newton, a thin subtle matter much fner and rarer than air (Mottelay, 1922).

With the development of the electric machine, the experimental electrophysiology began and developed

in the middle of the seventeenth century. Jan Swammerdam (1637–1682), a Dutch anatomist, natural

philosopher, developed a neuromuscular preparation in 1664. He studied the volume change of frog

muscles during contraction. Te muscle was immersed in water and caused to contract by pressure

applied to the nerve. Te level of the water fell slightly as the muscle contracted, thus showing that the

volume of the muscle had decreased rather than increased (Rowbottom and Susskind, 1984). His experi­

ments remained unknown until Galvani’s discovery of animal electricity. Trough Swammerdam, the

Germans claim to be the origin of what has been called galvanism (Mottelay, 1922). Experimental expla­

nation for the electric nature of action potential was provided many years later.

2.3 Development of Bioelectromagnetism

During the period from the beginning of the eighteenth century to the frst half of the nineteenth century,

the study of electricity and magnetism had rapidly developed which made progress in electromagnetism

and bioelectromagnetism. Tese developments led also to the application of electromagnetic phenomena

in industry and medicine (Fleming, 1921). Ten, the total electrifcation concept of the world gradually

proceeded and humans began to live in an anthropogenic electromagnetic environment in addition to

the naturally originated electromagnetic environment. Te essential history of electricity and bioelec­

tricity is briefy introduced to understand the source of bioelectromagnetism. Te research progress of

electricity during the Edo period in Japan is reviewed shortly as an interesting topic of electricity.

2.3.1 Development of Electricity

Ewald Georg von Kleist (1700–1748), a German inventor, dean of the cathedral chapter of Kamin in

Pomerania, Germany, invented a primitive form of a condenser in 1745. His condenser collected electric

charge from the atmosphere. Te condenser contained mercury or alcohol. At the same time, Pieter van

Musschenbroek (1692–1761), professor of physics at the University of Leyden, the Netherlands, refned it

with caution. His great caution was that a glass jar containing a metal rod was flled with water, which

can store electric charge. Tis invention became to be the modern condenser, called Leyden jar afer its

birth place, Leyden. Tis Leyden jar provided to be a useful tool for the research of electricity until the

discovery of Voltaic piles. Van Musschenbroek chose water; the most readily procured non-electric, and

placed some in a glass bottle. As shown in Figure 2.2, no important results were obtained until Cunaeus,

a pupil of Musschenbroek, an eminent philosopher of Leyden, burgess of Leyden, who while holding

the bottle, attempted to withdraw the wire which connected with the conductor of a powerful electric

machine. He received a severe shock in his arms and chest just afer touching the wire dipped in the

water (From Deschanel, 1876; Mottelay, 1922).