380 



TABLE 377.— THERMOELECTRIC EFFECT (concluded) 



Thermoelectric effect 



A 



Substance Microvolts 



Aluminum — .76 



Antimony, comm'l pressed wire.. — 



axial — 



equatorial — 



Argentan — 1 1.94 



Arsenic — 



Bismuth, comm'l pressed wire... — 



pure "... — 



crystal, axial — 



" equatorial — 



Cadmium + 2.63 



fused — 



Calcium — 



Cobalt — 



Constantan — 



Copper + 1-34 



" commercial — 



" galvanoplastic — 



Gallium — 



Gold + 2.80 



Iron +17.15 



" pianoforte wire — 



" commercial — 



Lead — 



Magnesium -f- 2.22 



Molybdenum — 



Mercury — 



Nickel — 



" (-18° to 175°) -21.8 



" (250°-300°) —83.57 



" (above 340°) - 3.04 



Palladium — 6.18 



Phosphorus (red) — 



Platinum — 



(hardened) + 2.57 



(malleable) — .60 



wire — 



another specimen — 



Platinum-iridium alloys: 



85% Pt + 15% Ir 7.90 



90% Pt + 10% Ir + 5.90 



95% Pt+ 5% Ir + 6.15 



Selenium — 



Silver + 2.12 



" (pure hard) — 



" wire — 



Steel +11.27 



Tantalum — 



Tellurium * B — 



a — 



Thallium — 



Tin (commercial) — 



" !!"!!!!!!!!""!!!!!!"!!."— .43 



Tungsten — 



Zinc + 2.32 



" pure pressed — 



* Electrical conductivity of Te. — 0.04, Te — 1.7 



SMITHSONIAN PHYSICAL TABLES 



