246 



SCIENCE. 



[N. S. Vol. XX. No. 503. 



Jordan's remarks apply to the species resem- 

 bling P: bolcanus. 0. E. Eastman. 

 Haevaed Universitt, 

 Cambbidse, Mass. 



the ascent of water. 



To THE Editor op Science : The identity be- 

 tween leaves and roots of trees which is signal- 

 ized by the criticism in your last issue prob- 

 ably signifies that they have the same sort of 

 resemblance as the entrance and exit of a 

 building. But the critic can not be entirely 

 ignorant of the recent researches which estab- 

 lish their antithetical relation so far as the 

 contention of my paper is concerned. Near 

 the leaves the ducts have an extreme vacuum, 

 so long as transpiration from the leaf-surface 

 continues ; this vacuum diminishes downwards 

 towards the base of the stem, as in a suction 

 pump ; and the inward current of water at the 

 base is still dependent (when root-pressure is 

 inactive) on a diSerence between the atmos- 

 pheric pressure and the tension within the 

 ducts. The results and authorities are sum- 

 marized in Pfeffer's ' Physiology,' also in E. B. 

 Copeland's paper in Botanical Gazette (Oc- 

 tober 19, 1902), and in Livingston's valuable 

 book on 'The Role of Diffusion.' Whilst 

 using these results my paper added nothing to 

 them. Its only aim was to remove a stum- 

 bling block which was caused by the tortious 

 assumption that atmospheric pressure can not 

 lift water more than 1033 centimeters high. 

 As the mixture of air and water within the 

 ducts appears to be in the condition of foam, 

 such pressure probably suffices to elevate it to 

 the top of the loftiest trees. This is the part 

 that ought to be criticized. 



I am much obliged to the editor of Science 

 for permitting me to submit the facts to his 

 great constituency. And now I wish to with- 

 draw from the case, and to leave its further 

 consideration to others. G. Macloskie. 



Princeton Univeesitt, 

 August 8, 1904. 



ANALYSIS OF A COMPLEX MUSICAL TONE. 



The analysis of a musical tone by means of 

 Helmholtz's resonators makes a good lecture 

 experiment when so carried out as to be heard 



by a large audience. Whether this has been 

 accomplished by others I do not know, but I 

 have succeeded as follows: A telephone re- 

 ceiver is connected to alternating - current 

 lighting mains (frequency 133 cycles per sec- 

 ond) through a resistance sufficient to reduce 

 the current to about | ampere. The tele- 

 phone then emits a tone having a funda- 

 mental pitch of 266 vibrations per second, 

 and of which the overtones are prominent. 



An adjusted resonator held over the mouth 

 of the telephone strengthens the overtone to 

 which it is tuned so as to make the overtone 

 easily audible throughout a large room. 



I have had no difficulty in demonstrating 

 eight successive overtones in this way. 



W. S. Franklin. 



SPECIAL ARTICLES. 



THE EFFECT OP RADIUM RAYS ON THE COLON 



BACILLUS, THE DIPHTHERIA BACILLUS 



AND YEAST. 



The discovery that tays emitted from salts 

 of radium may be used therapeutically in the 

 treatment of some diseases, has opened an in- 

 teresting field for conjecture as to the manner 

 in which these rays act, and naturally suggests 

 experiments concerning their effect on bacteria 

 in general, and especially on specific micro- 

 organisms. 



A few investigators have already published 

 results of such experiments. Pfeiffer and 

 Friedberger,* for example, found that typhoid 

 fever bacilli were destroyed by exposure to the 

 action of radium rays for forty-eight hours 

 at a distance of about 1 cm., but not at 5 cm. 

 distance. They found further that the bac- 

 teria only were affected, and that the culture 

 medium remained unchanged. Anthrax spores 

 dried on silk threads were destroyed after ex- 

 posure for three periods of twenty-four hours 

 each, but not after two twenty-four-hour ex- 

 posures. G. Bohnf has also reported that 

 ' lower organisms ' are quickly destroyed by 

 the action of radium rays. 



* Pfeiffer, R., and Friedberger, E., ' Ueber die 

 bakterientotende Wh-kung der Radium-Strahlen,' 

 Berl. hlin. Wochenschrift, 1903, No. 28. 



t Bohn, G., ' A propos de I'action toxique de 

 I'emanation du radium,' Soc. Biol., 55, p. 1655. 



