Hormell — Dielectric Constant of Paraffins. 



445 



Table VI. 



Kind of 



Observed 

 melting 



Density. 



l/2A=40-84 cm . 



l/2A=30'66 cm . 



l/2A=20-84 cm . 



;i=-00005896 cm . 



paraffin. point. 



P 



K 



H- 



K 



/" 



K 



/* 



K 



No. 120 



47-6° C. 



•894 



1-46(2) 



2-13(7) 



1-47(0) 



216(1) 



1-48(8) 



2-21(7) 



1-5380 



2-3655 



No. 125 



50-2° C. 



•905 



1-47(3) 



2-18(0)1 



1-48(9) 



2-21(8) 



1-50(4) 



2-26(2) 



1-5430 



2-3808 



No. 130 



53-3° C. 



•907 



1-48(3) 



2-19(8) 



1-49(3) 



2-22(0) 



1-50(2) 



2-25(6) 



1-5505 



2-4044 



No. 135 



56-2° C. 



•897 



1-49(0) 



2-22(1) 



1-50(1) 



2'25(4) 



1-51(2) 



2-28(6) 



1-5523 

 1-5050 



2-4098 

 2-2650 



Paraffin 



















1-4565 



2-1711 



oil 



309°flash 



•905 



1-54(3) 



2-38(1) 















Trans- 























former 























oil 





•823 



1-48(7) 



2-21(3) 















the dielectric constants for any given substance will reveal the 

 fact that in every case there is a gradual increase as the wave 

 length decreases, even including the light wave. These results 

 certainly indicate the analogous behavior of electrical and light 

 waves. A comparison of the dielectric constants of the differ- 

 ent paraffins shows that these constants increase with the melt- 

 ing point. From these experiments it seems necessary, there- 

 fore, in tabulating the dielectric constant of paraffin, to give its 

 density, its melting point, and the wave length for which the 

 constant was obtained. The third decimal place is bracketed 

 because the accuracy of measurements does not warrant its 

 unqualified use, and yet the quantities of which the tabulated 

 numbers are the average are of such uniformity that some 

 credence must be given to this third place. 



Light Index of Refraction. 



The light index of refraction was obtained by means of an 

 Abbe* refractometer. This is constructed upon the principle 

 of total reflection and is graduated to read directly the index 

 of refraction of the D x line of any transparent liquid or solid 

 which can be placed between its prisms. Films of paraffin 

 were easily procured by floating bits of wax on hot water and 

 allowing the melted wax to solidify. In order to insure close 

 contact, both the film and the prisms were gently heated before 

 the wax was placed before the prisms. The refractometer gave 

 data also from which by means of a table one could calculate 

 the dispersion factor between the D x and the F lines. 



Having the index of refraction for two lines in the spectrum, 



* Physikalischer Praktikum, Wiedemann-Ebert. 



