940 BIOLOGICAL EFFECTS OF RADIATION 



intensity of the mitogenetic rays. Rajewsky (224) reports their inten- 

 sity, as obtained from tests in the modified Geiger counter, as about 10 

 to 100 quanta/cm. 2/sec. Frank and Rodinow (79) report 100 to 1000 

 quanta/cm. 2/sec. It seems that the intensity might be regarded as 

 closer to Rajewsky's calculation, and in fact several investigators claim 

 that Rajewsky's calculations are too high. If, however, we accept 100 

 quanta/cm. 2/sec. as a possible figure and use a slit of 0.4 mm. width and 

 a time of exposure of 2 min., we have a total of 480 quanta. And if we 

 suppose that 50 per cent of the radiation is lost in the spectrograph, we 

 have 240 quanta left. We divide this into 30 bands (nerve radiation) 

 and we have for each band 8 quanta. Each detector tube covers about 

 one-third of the exit slit. Each liquid detector culture would then get a 

 total of 3 quanta in 2 min. This total of 3 quanta is supposed to be 

 enough to cause 0.5 cc. of yeast suspension to show a growth increase of 

 20 per cent. Of course, it may be possible that the energy estimations 

 are too low and it is also possible that living materials respond to energy 

 for which we have as yet no equivalent in physics. 



BIOLOGICAL SENDERS 



As mentioned in the introduction, there are several hundred publica- 

 tions on the application of the mitogenetic-ray method to the study of 

 biological problems. Problems offering real possibilities have been 

 investigated; on the other hand, many problems which have been 

 attacked are of the utmost complexity, as for instance, the work on nerve 

 physiology, the work on blood, and on cancer. An idea of the type of 

 work which has been attempted, and for which success is not infrequently 

 claimed, may be obtained from a glance at the titles in the literature list; 

 the reviewer must leave to specialists in these several fields as to whether, 

 from this work, we should indulge our hopes or our sorrows. 



We shall attempt, as far as it seems feasible at present, to bring all this 

 work under a common schema as it were. In doing this we shall for the 

 time being accept all the results as definite, and all doubts about the 

 reliability of the technique or about the experimental procedure will be 

 ignored while attempting to review it as a proponent might. 



In most of the newer work published from the Gurwitsch school, a 

 spectral interpretation of the source is attempted. In other words, the 

 mitogenetic-emission spectrum is determined and the spectra are com- 

 pared with the established spectra of fundamental reactions. There are 

 three fundamental reactions which give typical spectra: oxidation, 

 proteolysis, and glycolysis. It is not necessary that in a biological reac- 

 tion a complete fundamental spectrum appear; it sometimes happens 

 that only the major band will be recognizable. The spectra given in 

 Fig. 6 are partly obtained by biological reactions and partly by purely 

 chemical reactions, as the spectra given are typical. One must not rely 



