100 



Tables 76-77. 

 ELA3TIC MODULI. 



TABLE 76.— Elgidity Modulus. 



If to the four consecutive faces of a cube a tangential stress is applied, opposite in direction on 

 adjacent sides, the modulus of rigidity is obtained by dividing the numerical value of the tangential 

 stress per unit area (kg. per sq. mm.) by the number representing the change of angles on the 

 non-stressed faces, measured in radians. 



Substance. 



Aluminum 



" cast .... 

 Brass 



" cast, 6o Cu-|- 12 Sn 

 Bismuth, slowly cooled . 

 Bronze, cast, 8b Cu + 12 Sn 

 Cadmium, cast .... 

 Copper, cast 



Gold. ..'.'...'. 

 Iron, cast 



Magnesium, cast . . . 



Nickel 



Phosphor bronze ... 



Substance. 



Quartz fibre . . . 

 Silver 



" hard-drawn . 

 Steel 



" cast . . . . 



" cast, coarse gr. 



" silver- . . . 

 Tin, cast . . . . 



Zinc 



it 



Platinum . . . . 



Glass 



Clay rock . . . . 



Granite 



Marble 



Slate 



Rigidity 

 Modulus. 



2888 

 2380 

 2960 

 2650 

 2566 

 2816 

 8290 



7458 

 8070 

 7872 

 1730 

 1543 

 38S0 

 3820 

 6630 

 6220 



2350 

 2730 

 1770 

 1280 

 1 190 

 2290 



Refer- 



20 

 21 



s 



10 



16 



II 



16 

 15 



5 

 II 



5 

 19 



5 



19 

 16 

 22 



23 

 23 

 23 

 23 



References 1-16, see Table 48. 



17 Gratz, Wied. Ann. 28, 1886. 



18 Savart, Pogg. Ann. 16, 1829. 



19 Kiewiet, Diss. Gottingen, 1886. 



20 Threlfall, Philos. Mag. (5) 30, i{ 



21 Boys, Philos. Mag. (5) 30, 1890. 



22 Thomson, Lord Kelvin. 



23 Gray and Milne. 



2a. Adams-Coker, Carnegie Publ. No. 46, 

 1906. 



TABLE 77. — VarlaUoa o2 tlie Rigidity Bdodnltis with the Temperature. 



f!f = «„ (i — a( — 0('^ — 7/^), where / == temperature Centigrade. 



Substance. 



Brass . 



Copper . 



Iron . . 



Platinum 

 Silver . 

 Steel . 



2652 

 3200 



3972 

 3900 

 8108 

 6940 

 6632 

 2566 

 8290 



BIO* Pio' yio*' 



2158 



455 

 2716 



572 

 206 



483 

 III 



187 



36 

 -23 



28 



19 

 12 



5° 

 38 

 59 



32 

 47 

 -II 



II 



—9 



Authority. 



Pisati, Nuovo Cimento, 5, 34, 1879. 



Kohlrausch-Loomis, Pogg. Ann. 141. 



Pisati, loc. cit. 



K and L, loc. cit. 



Pisati, loc. cit. 



K and L, loc. cit. 



Pisati, loc. cit. 



«i* = "i5 [i —a(e — 15)]; Horton, Philos. Trans. 204 A, 1905. 



Copper 



Copper (com- 

 mercial) 

 Iron 

 Steel 



4-37' 



3.80 

 8.26 

 8.45 



a =.00039 



.00038 

 .00029 

 .OCO26 



a = .0001 2 

 .00031 

 .00048 

 .00148 



a = .00416 

 .00164 

 .0058 

 .00012 



Sm'thsonian Tables. 



* Modulus of rigidity io so** dynes per sq. cm. 



