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National Coal Board methane drainage pipe calculator with pouch
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National Coal Board methane drainage pipe calculator with pouch, c.1973.
Details
- Category:
- Coal Mining
- Collection:
- Lancashire Coal Mining Collection
- Object Number:
- Y2002.19.485.3
- Measurements:
-
195 mm,
- type:
- circular slide rule
- credit:
- Gift of Salford Museum and Art Gallery