332 



SCIENCE. 



[N. S. Vol. XXIII. No. 583. 



bromide of 1,500,000 and of 10,000 activity 

 in a sealed glass tube, for twelve hours or 

 more, germination and subsequent growth 

 are retarded. If the same radium prepara- 

 tions are inserted in the soil in pots con- 

 taining germinating seeds, there is a de- 

 cided acceleration of germination and 

 growth. In such plants there is a marked 

 increase in the number and length of 

 root-hairs. 



When plants are grown under a bell-jar 

 containing decaying radium emanation 

 drawn from a hollow tube lined with 

 Lieber's radium coating, germination and 

 growth are either retarded, completely in- 

 hibited, or acceleratel, according to the 

 amount of the emanation supplied, and the 

 duration and distance of exposure. 



When the stimulation is of such intensity 

 as to accelerate growth, the rate of growth 

 at first increases, and then gradually de- 

 creases imtil it falls below that of the con- 

 trol plants. 



Marked anatomical changes are effected 

 by exposure to the rays, the cross-section 

 of the stem of a radiated plant, for ex- 

 ample, showing no signs of cambium. 



Respiration and alcoholic fermentation 

 may be accelerated. By strong exposure 

 ehloroplasts in the cell take up a position 

 similar to that as-sumed under intense sun- 

 light, and eventually the radiated portion 

 becomes etiolated. 



It is hoped to be able still further to 

 study the effect of the rays on cell activities 

 by means of radioactive microscopic slides 

 now being prepared at the writer's sug- 

 gestion by Mr. Hugo Lieber, of New York. 

 Grateful acknowledgment is here made of 

 Mr. Lieber's liberality in supplying some 

 $2,000 worth of radium preparations, with- 

 out which these experiments would not have 

 been possible. 



Experiments to Determine the Effects of 

 Radium on Minute Animals: L. Hus- 



SAKOF. 



These experiments were intended pri- 

 marily to show the influence, if any, of 

 radium rays on the protoplasm of Amoeia 

 proteus. Other microorganisms {Vorti- 

 cella, Paramcecium, etc.) were also subjects 

 of experiment. Radium bromide prepara- 

 tions of 600, 1,000, 10,000 and 1,500,000 

 activity (in thin glass tubes) were used, 

 and several celluloid rods covered with 

 Lieber's 'radium coatings' of 10,000 to 

 25,000 activity were also employed. The 

 radium container was held in the water 

 within from 1 mm. to 3 mm. of the organ- 

 ism under observation. 



Under these conditions no visible effects 

 were produced, by even the strongest 

 radium preparations, during periods of ob- 

 servation of about an hour. The water 

 surrounding the animal may have pre- 

 vented radiant effects. 



The Effects of Intravenous Injectio^i of 

 Radium Bromide in Dogs: R. B. Opitz 

 and G. M. Meyer. 



The paper dealt principally with effects 

 on circulation and respiration. Light ether 

 narcosis was employed. With radium 

 bromide of 240 and 1,000 activity there was 

 a marked rise in blood pressure, caused by 

 a general vaso-constriction, followed by a 

 marked decrease in the frequency of the 

 heart, causing fall in pressure. These effects 

 are the same as obtained with pure barium 

 bromide. With radium bromide of 10,000 

 activity there was a much less noticeable 

 initial vaso-eonstriction, and the short 

 forcible contractions of the heart which 

 caused the pressure to rise suddenly in 

 jerks beyond any ordinary level, are now 

 succeeded by slow pulsations. The blood 

 pressure thus remained below normal. A 

 moderate decrease in the frequency and 

 depth of respiration was noted. 



The Radioactivity of the Organs of Dogs 

 after Administration of Radium Bro- 

 mide: G. M. Meyer. 



