87G 



DE. A. MATTIUESSEN ON THE EXPANSION 



Table X. 



Observed vol. at 0'=1, Calculated vol. at 0- = l, 



Vol. per cent. then vol. at 100P= then vol. at 100'= 



Sn^ Pb 22-28 of Pb 1-007188 1-007225 



Pb, Sn 82-09 of Pb 1-008419 1-008128 



Cd Pb 58-49 of Pb . 1-009138 1-008847 



Sn^Zn 87-46 of Sn 1-007184 1-007144 



Sne Zn 91*28 of Sn 1-007058 1-007066 



Bi„ Sn 0-85 of Sn 1-0040G4 1-003972 



Bi Sn, 43-81 of Sn 1-005098 1-005207 



Bi.„Pb 1-76 of Pb 1-004086 1-004026 



Bi Pbj 46-26 of Pb 1-008621 1-006007 



Cu+Zn (71 percent. Cu). 33-85 of Zn 1-005719 1-006328 



Au Sn, 60-85 of Sn 1-004233 1-005919 



Au, Sn., 73-14 of Sn 1-004428 1-006223 



Ag, Au 19-86 of Au 1-005166 1-005549 



Ag Au 49-79 of Au 1-004916 1-005123 



Ag Au, 79-86 of Au 1-004300 1-004693 



Ag + Pt (66-6 per cent. Ag) 19-65 of Pt 1-004568 1-005207 



Au + Cu(66-6percent.Au) 48-06 of Au 1-004657 1-004716 



Ag+ Cu (36-1 percent. Ag) 28-31 of Ag 1-005436 1-00533 



Ag+ Cu (71-6 per cent. Ag) 71-13 of Ag 1-005713 1-00507. 



In Table XI. the equivalents and specific gravities used for the foregoing calculations 

 are given. 



Table XI. 



Metal. Equivalent, Specific gravity. 



Cadmium 56-0 8-655 



Zinc 32-6 7-148 



Lead 103-7 H-376 



Tin ....... , 58-0 7-294 



Silver 108-0 10-468 



Copper 31*7 8-950 



Gold 197-0 19-265 



Bismuth 208-0 9-823 



Platinum 21-400 



On comparing the observed with the calculated volumes, we find that they mostly 

 agree together as well as may be expected, considering that the observed values cannot 

 be deemed absolutely correct, and that a difference in the ciystalline form will in all 

 probability cause a slight difierence in the coefficients of expansion. It is well known that 

 alloys crystallize much more readily, in most cases, than the component metals, and not 

 always in the same form. The difibrence between the observed and calculated values 

 obtained for. the alloy BiPbo is so great that I thought some error had occurred in 

 making the alloy; I therefore remade it, redetermined the coefficient of expansion 

 (Series No. 42), and obtained the same values. That the gold-tin alloys have lower 

 coefficients of expansion than those of the mean of the component volumes of the metals 



