172 Mr. C. Barus on the Viscous Effect of 



Table VIII. — Viscous results for the Hnrd and Soft Wires 

 in Tables IV., V., VI., VII. 







T. 



Drawn. 



Soft. 



e. 







Drawn. 



Soft. 



A-^-^'xlO^ 



A'^-'^'xlO^. 



r. 



A'^-^'xm^ 



A^~^'xl0\ 







r 



T 



30 



+ •10 



T 



r 



30 



+ •10 



ro8 



•10 



4 37 



•00 



30 



-■10 



-1-01 



-00 



30 



-•09 



- 4-72 



-•10 



100 



+ •10 



2^83 



•33 



100 



+ •09 



10-.50 



•47 



100 



-•09 



-303 



-•33 



100 



-•09 



- 9-50 





0. 



r. 



1 

 Drawn. 



tg- 





T. 



Stretched. 



A^~^'-10« 



^ 



1 



.^-^'xio^ 



T 







T 











30 



+ •10 



+2^62 









•10 





+ 03 



30 



-•10 



-2^70 



2^4 





•10 





+ •06 



30 



+ •10 



+r6i 



4^8 





•10 





+•07 



30 



-10 



-r42 



84 





•10 







30 



+ •10 



+ 126 













From this table the small efiect of traction in case of loads 

 below 25 per cent, of the breaking stress is specially mani- 

 fest; an effect negligible in comparison with the diminution 

 of viscosity due to the drawn strain. For the sahe of orienta- 

 tion I may assume that corresponding values of A{(f) — (f)')/T 

 for glass-hardness would at 30° be about 1/10' to 2/10' ; that 

 is, about equal to this quantity in the case of a moderately re- 

 silient wire. In general the results for the drawn strain both 

 at 30'^ and at 100° corroborate and accentuate the results 

 already obtained for temper*, so that the further discussion 

 can be made as in my earlier papers, and may be waived here. 

 I add only that the effect of drawing in case of steel is a de- 

 crease of the density of the soft metal ; for instance, 

 Eods ". A. 



Originally soft . . . 7'76 



Drawn very resilient . 7*72 



Softened after drawing 7'80 

 It appeal's that in this respect also 

 temper are similar. 



* Phil. Mag. [o] xxvi. p. 205 ei seq., 1888. 



B. 



C. 



7-72 



7-68 



7-64 



7-64 



7-73 





ic drawn 



strain and 



