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Non-Conductor. | Value.
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Wood Felt | 1.000
Mineral Wool No. 2 | .832
Do. with tar | .715
Sawdust | .680
Mineral Wool No. 1 | .676
Charcoal | .632
Pine Wood, across fibre| .553
Loam, dry and open | .550
Slaked Lime | .480
Gas House Carbon | .470
Asbestos | .363
Coal Ashes | .345
Coke in lumps | .277
Air space, undivided | .136
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