Scientific Study of Unidentified Flying Objects (the Condon Report, complete, three volumes)

to enable it to retain a substantial degree of permanent
magnetism. Thus, it ordinarily will retain a substantial
portion of the earth's magnetic field as it existed at the
time of forming. This can easily be demonstrated by ham-
mering a nail on an anvil, with the nail pointing north/
south, which will result in permanently magnetizing the
nail in the direction of the earth's field.
The external sheet metal parts of an automobile, such
as the door panels, hood, deck lid, roof, and minor body
panels, are orJinarily formed under conditions that remain
constallt for the duration of the yearly model, and often
for t~ree or four years. Thus, the parts of a given make
and model car are all likely to have corne from a single
source, or at the most two sources, no matter ·"here the
car is assembled. The dies that form these parts orJluarily
remain un~~sturbed during the service life, subject to
repeated blows that cause them to become magnctizcJ by the
magnetic field of the earth, and forming parts that all
take on a similar pattern of magnetism.
Other processes that leave their magnetic imprint on
the sheet metal parts of the car, are the use of magnetic
lifting devices, spot.,welding, and (where used) \:hrolilc"
plating~ with the result that each make anJ model c<lr has
a p<lttern of magnetism retained in its sheet motal r<.'rts
that is as (\istinctive of that make and moud as a finger
print is of an individual.
This characteristic was utilized in the tests reported
in Case l~, as a suggested technique whereby vehicles could
be examined for some indi~ation of th~ir history so far as
magnetic environment is cc.mcerned. The vehi.cle wa:- carefUlly
mapped with a magnetometer, and the compl~x pattern of mag-
netic remanence WRS compared with that of three other vehicles
of thp. same mS13, model, and year cho~en at random. It proved
154
to enable it to retain a substantial degree of permanent
magnetism. Thus, it ordinarily will retain a substantial
portion of the earth's magnetic field a~ it existed at the
time of forming. This can easily be demonstrated by ham-
mering a nail on an anvil, with the nail pointing north!
south. which will result in permanently magnetizing the
nail in the direction of the earth's field.
The external sheet metal parts of an automobile, such
as the door panels, hood, deck lid, roof, und minor body
panels, are ordinarily formed under conditions that remain
constallt for the duration of the yearly model, and often
for three or four years. Thus, the parts of a given make
and model car are all likely to have come from a single
source, or at the most two sources, no matter·~here the
car is assembled. The dies that form these parts ol"J1Iiarily
remain un~~sturbed during the service life, subject to
repeated blows that cause them to become magnetized by the
magnetic field of the earth, and forming parts that all
take on a similar pattern of magnetism.
Other processes that leave their magnetic imprint on
the sheet metal parts of the car, are the use of magnet:\c
lifting devices, spot-welding, and (where used) chrome-
plating, wi th the resul t that each make and mode:] c.n hilS
a pattern of magnetism retained in its sheet metal F'Tts
that is as ~istinctive of that make and mouel as a finger
print is of all individual.
This characteristic was utilized in the tests reported
in Case l~, as a suggested technique whereby vehicles could
be examined for some indication of th~ir history so far as
magnetic environment is ctmcerned. The vehi.cle wa!' carefully
mapped with a magnetometer, and the complex pattern of mag~
netic remanence WI\S compared with that of three other vehicles
of the same ma~3, model, and year cho~en at random. It proved
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