568 



SCIENCE 



[N. 8. Vol,. XLI. No. 1059 



years, then falling steadily until the age of 19. 

 From this point there is very slight decrease be- 

 fore old age is reached. During convalescence 

 from typhoid fever the curve of metabolism is 

 similar to that of childhood. The evidence points 

 towards an increased metabolism of growing tissue. 

 The fact that the liver and thyroid gland are rela- 

 tively large in children may account for part of the 

 increase. 



I. S. Kleinek and S. J. Meltzer: 'Retention in the 

 Circulation of Injected Dextrose in Depancrea- 

 tized Animals and tlie Effect of an Intravenous 

 Injection of an Emulsion of Pancreas upon this 

 Retention. Preliminary communication. Pre- 

 sented by S. J. Meltzer. 



When dextrose is injected intravenously into 

 normal animals, even in large quantities, it disap- 

 pears rapidly from the circulation, and the sugar 

 content of the blood is, in a short time, quite nor- 

 mal again. In previous investigations the authors 

 found that in depancreatized dogs there is a tend- 

 ency for the circulation to retain for a longer 

 period a part of the injected dextrose. In recent 

 experiments it was further found that, when with 

 the infusion of dextrose in depancreatized dogs an 

 emulsion of pancreas is simultaneously injected, 

 the circulation seems to lose its power to retain 

 the injected dextrose. These experiments seem, 

 therefore, to show that the power of the circula- 

 tion to rid itself of a surplus of sugar is due to 

 the influence of an internal secretion of the pan- 

 creas. 

 E. A. MiLLiKAN : Atomism in Modern Physics. 



Atomism in modern physics begins vrith Dal- 

 ton's discovery in 1803 of exact multiple rela- 

 tionships between the combining powers of the ele- 

 ments. Out of this discovery grew the whole of 

 modern chemistry. The second tremendously im- 

 portant step was taken in 1815 when Prout pointed 

 out that the atomic weights of the lighter elements 

 appeared to be exact multiples of that of hydrogen, 

 thus suggesting that hydrogen was itself the pri- 

 mordial element. The periodic table of Mendeleef 

 added support to such a point of view, and Mos- 

 ley's recent brilliant discovery through the study 

 of X-ray spectra of a new series of multiple rela- 

 tionships, represented by a consecutive series of 

 atomic numbers from 13 up to 79 with every num- 

 ber except three corresponding to a knovm element, 

 is another most significant bit of evidence. When 

 we add to this three other facts, namely, (1) that 

 each member of a radioactive family, like the 

 uranium family, has been definitely shown to be 

 produced from its immediate ancestor by the loss 



by that ancestor of one atom of helium (which is 

 almost equal in weight to four atoms of hydrogen), 

 (2) that in an atomic weight table the differences 

 between the weights of adjacent elements are in 

 almost every case exact multiples of the weight of 

 the hydrogen atom, the characteristic helium dif- 

 ference 4 appearing with extraordinary frequency, 

 and (3) the fact that the introduction of the con- 

 cept of electro-magnetic mass, and the consequent 

 discovery of the inconstancy of mass, open several 

 ways of explaining the slight departures in the 

 exactness of the multiple relations between atomic 

 weights pointed out by Prout, it will be evident 

 that modern science may well feel fairly confident 

 that it has indeed found in hydrogen the primor- 

 dial atom which enters into the structure of all 

 the elements. All this is merely a very modern 

 verification of very ancient points of view. 



But modern physics has recently taken a more 

 significant and more fundamental step than this, 

 for it has looked inside the atom with the aid of 

 X-rays and other ionizing agents, and has there 

 come upon electrically charged bodies, whose in- 

 ertia or mass is wholly accounted for, at least in 

 the case of the negative elements, by their charges. 

 This discovery marks the fusing into one another 

 of two streams of physical investigation, namely, 

 the molecular stream and the electrical stream. A 

 necessary condition for the justification of this 

 last step was the bringing forward of indubitable 

 proof that the thing which has heretofore been 

 called electricity is after all, contrary to Maxwell's 

 view, a definite material substance in the sense 

 that it exists in every charge in the form of dis- 

 crete elements ; in other words, that it too like mat- 

 ter is atomic or granular in structure. Such proof 

 was found in the discovery in the oil drop experi- 

 ments of even more exact multiple relationships be- 

 tween all the possible charges which can be put on 

 a given body than Dalton had ever discovered be- 

 tween combining powers or Prout between atomic 

 weights or Moseley between X-ray frequencies. 

 The greatest common divisor of this series of 

 charges is then the ultimate unit or atom of elec- 

 tricity which has been named the "electron." 

 New evidence that it is indeed a universal and in- 

 variable natural constant will be brought forward 

 and a new determination of its value will be pre- 

 sented. 



It is obvious that as soon as we could assert that 

 these electrons are found in the hydrogen atom it 

 was necessary to suppose that a single hydrogen 

 atom contains at least two such electrons, one 

 positive and one negative, and as a matter of 



