File:PSM V74 D233 Thorium radioactive incandescent gas mantle placed above plant seeds.png

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Summary

Description	English: Thorium radioactive incandescent gas mantle placed above plant seeds
Date	1909
Source	Popular Science Monthly Volume 74 (January to June 1909), Page 229, Fig. 8.
Author	Unknown Unknown author

Experiment on the effect of radiation (from unburned thorium gas mantle) on the germination and growth of timothy grass seed.

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