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US2848829A
|
|
Illuminated warning signal or sign
|
|
US2578806A
|
|
Propeller
|
|
US2585249A
|
|
Clip for holding electrical conducting wires to insulating supports
|
|
GB617792A
|
|
Improvements in or relating to magnetic particles for crack-detecting fluids, the production of such particles, and fluids containing such particles
|
|
GB551355A
|
|
Improvements in or relating to the control of magnetic circuits
|
|
GB547991A
|
|
Improvements in or relating to apparatus for the detection of cracks in ferrous metals by magnetic means
|
|
GB502973A
|
|
Improvements in fluids for the detection of cracks in ferrous metals by magnetic means
|
|
US1384389A
|
|
Apparatus for testing the hardness of materials
|
|
GB140165A
|
|
Improvements in apparatus for testing the hardness of materials
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