August 1, 1902.] 



SCIENCE. 



177 



Contributions to the History of Blusical 

 Scales: Chas. K. Wead, Washington, 

 D. C. 



This paper was a summary of a research 

 just published in tlie 'Report of the U. S. 

 National Museum' for 1900. It described 

 some forms of four-hole resonators found 

 in various museums that give a pentatonie 

 scale, whose notes have vibration fre- 

 quencies following a sqiiare-root law; and 

 various flutes and fretted string instru- 

 ments were cited that show an equal linear 

 division. The conclusion was that the 

 primary principle of instruments capable 

 of giving a scale is the repetition of ele- 

 ments similar to the eye ; so the instrument 

 is the first thing, the scale a secondary 

 thing. Theoretic scales belong to a much 

 later stage of culture. 



The Present Significance of Enharmonic 

 Musical Instruments: Chas. K. Wead, 

 Washington, D. C. 



These instruments may, in the hands of 

 an artist, furnish a new point of view from 

 which to judge of the development of music 

 and its possibilities. But there is no evi- 

 dence that any important music was ever 

 composed in just intonation or that any of 

 the many proposed - or patented instru- 

 ments are fitted to express the ideas of a 

 composer. Certainly the diatonic idea 

 which underlies such instruments is now 

 far less important than when Helmholtz 

 wTote, forty years ago. 



Preliminary Note on the Effect of Percus- 

 sion in Increasing Magnetic Intensity: 

 Geo. F. Stradling, Philadelphia. 

 When a rod of iron, steel or nickel has 

 been magnetized and then demagnetized 

 hy the passage of a current of proper 

 strength through the coil in which the rod 

 is placed, tapping the rod causes the 

 appearance of poles having the same direc- 

 tion as those existing before demagnetiza- 



tion. These poles, as the tapping continues, 

 grow in strength to a maximum and then 

 decrease. 



If the demagnetizing current more than 

 overcomes the original magnetism and pro- 

 duces poles in the opposite direction, still 

 the effect of tapping is to make them first 

 approach to those originally existing and 

 then recede. In this case there are three 

 stages produced by percussion : 



1. Lessening of pole strength to zero. 



2. Growth of pole strength in the direc- 

 tion existing before demagnetization. 



3. Decrease of the strength of these 

 newly acquired poles. 



Whether percussion increases or de- 

 creases pole strength depends on the pre- 

 vious magnetic history of the body ex- 

 amined. 



Preliminary Note on the Electrical Conduc- 

 tion' of Saturated Powders: N. E. 

 DoESEY, Annapolis Junction, Md. 

 The electrical conductivity of non-con- 

 ducting powders saturated with electrolytic 

 solutions was compared with the conductiv- 

 ity of the supernatant liquor. For coarse- 

 grained powders the two are proportional, 

 but when the powder is fine the conductiv- 

 ity of the saturated powder at first in- 

 creases more rapidly than that of the 

 supernatant liquor, with the result that 

 for quite dilute solutions the conductivity 

 of the saturated powder, as measured in a 

 cubical cell, a pair of whose opposite sides 

 served as electrodes, may even exceed that 

 of a volume of the supernatant liquor equal 

 to that of the solution in the powder as 

 measured in the same cell. 



Determination of the Vapor-pressure of 

 Mercury at Ordinary Temperatures: 

 Edwakd W. Morlet, Cleveland, Ohio. 

 The writer has determined the vapor- 

 pressure of mercury at intervals of ten de- 



