118 MR. F. C. CALVERT AND MR. R. JOHNSON 
The alloy Cu Zn possesses another remarkable property, 
viz., the facility with which it is capable of crystallising 
in prisms half an inch in length, of extreme flexibility. 
There is no doubt that this alloy is a definite chemical 
compound, and not a mixture of metals, as alloys are 
generally considered to be. Our researches on the con- 
ductibility of heat by alloys, which we have recently 
presented to the Royal Society, leave no doubt that many 
alloys are definite chemical compounds. 
On Bronze Alloys. 
Formule of Alloys and pe: tag Wiseht & Bg os ted 
r centages. employed. ast Iron ast Iron 
: = 1000 =1000. 
] lbs. 
Gulliag 4 or er ped. wails 400 83°33 | 51-67 
(Cu 11°86} 
Cu Sn, (Sn 88.14 f tte 460 95°81 59°56 
Cu 15°21) ! r 
Cu Sng { Peasaca pester ag: 500 10417 68°75 
Cu 21°21 ) 5 ; 
Cu Sn, { =e ae 650 135-42 84°79 
Cu Sn ' ae ae j bc > eaecpen ate At 700 Ibs. the point entered one half 
Cu 48-17 and the alloy broke. 
Sn Cu, \Sn 51°83} Me tleds« ih. At 800 lbs. the alloy broke without 
Cu 61-79 the point entering. 
Sn Cu, {Sn 38-2] } 1A ee At 800 lbs. the alloy broke into 
Ou 68-27 small pieces (blue alloy). 
SLT peak oo ie ai 1300 bs. divided the alloy into2 pieces 
Cu 72:90 withoutthe point havingentered lmm. 
Sn Cu; \Sn 27°10 phlei sie saat The same as the preceding. 
(Cu 84°32 
Sn Cujo} s, 15.68} 50h Cecens 4400 916-66 | 257-08 
{ Cu 88°97 f ; 
SL peace Se ee 3710 77292 | 27083 
Bn. Ougg fen Big tannieehe 3070 | 63958 | 277-70 
Cu 93:17 . . 
Bu Ong i, gga poten: 2890 | 60208 | 279-16 
The results obtained from this series of alloys lead to 
several conclusions deserving our notice. 
First, the 
marked softness of all the alloys containing an excess of 
tin; secondly, the extraordinary fact that an increased 
