CHAPTER V 

 BIO-RADIOACTIVITY, EOBES, RADIOBES 



I. The Supposed Radioactivity of Plants and of Wood 



Soon after the discoveries of "contact" electricity and "animal" 

 electricity by Volta and Galvani, plant physiologists began to look 

 for electric currents in plants, and to find therein the explanation of 

 " vital" activity. In a similar manner the announcement of the dis- 

 covery of radioactivity has been followed by numerous supposed 

 observations of a natural or acquired radioactivity of plants and 

 plant tissues. 



Professor A. B. Green" was among the first to report that micro- 

 organisms, especially species of Staphylococcus^ after an exposure 

 of from 24-120 hrs. to radium rays at a distance of 0.5 mm., them- 

 selves exhibit phenomena of radioactivity. He considers it uncertain 

 as to whether living organisms can acquire this property, but states 

 that those killed by the action of radium rays can do so. In his ex- 

 periments the radium salt was enclosed in a vulcanite and brass cap- 

 sule, and the radioactivity acquired by the organisms, lasted for 

 three minutes after the termination of the exposure, and enabled 

 them to photograph themselves on a sensitive plate. Their spores 

 were found to be best for this purpose. I have already discussed 

 these results on page 62. 



Lambert'^ stated in 1904 that ferments that digest albuminous 

 matter emit Blondlot rays, and that the emission of these rays is the 

 cause of the action of the soluble ferments. 



The experimental demonstration of the emission of the so-called 

 N rays by plants of the garden cress was reported by Meyer. Their 

 emission, he said, varies with the activity of the protoplasm, and is 

 diminished when the plants are exposed to the vapor of chloroform, 

 and is modified by mere compression of the tissues. 



In 1904 Russel ' described before the Ro3^al Society the rather 

 startling discovery of the action of wood on a photographic plate in 

 the dark. This property, he said, belongs probably to all woods. 

 Conifers are especially active, and the spring wood most of all, but 

 the dark autumn wood produced no such effect. Oak, beech, acacia 



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