222 On the Expansion hy Heat of Metals and Alloys, [June 21, 



Table IV. — Formulae for the Correction of the Linear Expansion by 

 Heat of the Alloys. 



Sn, Pb L, = L, (1 + 10-^ X 0-2066^ + 10-^ x 0-0329O. 



Pb^Sn L,=L„(l + 10-^xO-2696i+10-^xO-0111t2). 



CdPb L,=L,(l + 10-^xO-3002^+10-'xO-0044^^). 



Sn, Zn L,=Lo (I + IO"^ x 0-2126^+10-^ X 0-02691^^). 



Sn^Zn L, = L,(l + 10-^x0-2079^+10-^x0-0274O. 



Bi,^ Sn L,= L, (1 + 10-^ X 0-1264^+10-^ X 0-00900- 



Bi Sn, L,= L, (1 + 10-^ X 0-1666^+10-^ X 0-0034^^). 



Bi,, Pb L, = L„ (1 + 10-^ X 0-1293 + 10"^ x 0-0073^^). 



BiPb, L,=Lo (1 + 10-^x0-2821 +10-^x0-00530 

 Cu + Zn (71 p. c. Cu) L,=L„ (1+10"^ x 0-1720^+10-^ X 0-0086^^). 



Au Sn, L,= (1 + 10-^ x 0-1315^+10"^ X 0-0096f ). 



Au, Sn, L,= Lo (1 + 10-^ x 0-1388^+10-^ X 0-0088O. 



AgAu L,= Lo(l + 10-^xO-17220. 



AgAu L,= L, (1 + 10-^x0-16380. 



Ag Au, L,= L, (1 + 10-^ X 0-1038z;+ 10-^ X 0-0395O. 

 Ag+ Pt (66-6 p. c. Ag) L,= L, (1 + 10-^ x 0-1415^+10-^ x 0-0107^'). 

 Au+Cu (66-6 p. c. Au) Le= (1 + 10-^ x 0-1338^+10"^ x 0-0214f ). 

 Ag+ Cu (36- 1 p. c. Ag) L,= (1 + 10"^ x 0-1628^+10"^ x 0-0182f ). 

 Ag+Cu (71-6 p. c. Ag) L, = Lo (1 + 10"^ x 0-1471^+10"^ X 0-0433O. 



From the above the following conclusion is drawn — namely, that just as 

 it may be said that the specific gravity of an alloy is approximately equal 

 to the mean specific gravities of the component metals, so also from the 

 foregoing we may deduce that the volume which an alloy will occupy at 

 any temperature between 0° and 100° is approximately equal to the mean of 

 the volumes of the component metals at the same temperature, or, in other 

 words, the cubical or linear coefficients of expansion by heat of an alloy 

 between 0° and 100° are approximately equal to the mean of the cubical 

 or linear coefficients of expansion by heat of the component metals. 



V. On the Colouring and Extraction Matters of the Urine. — Part 

 II." By Edward Schunck, F.R.S. Received June 20, 1866. 



See abstract, antea, p. 1 . 



r 



