MR. S. W. J. SMITH ON THE TIIERMOM AG NET T C ANALYSIS OF 
of Ni cools from a temperature above 700° C., kamacite will form in gradually 
increasing amount until the eutectic temperature (below 100° C.) is reached. At 
this temperature the remainder of the material, containing the percentage of Ni 
represented by GB (fig. 23, p. 67), will separate as taenite, an intimate mixture of 
kamacite containing GE per cent, of Ni and of a more nickeliferous alloy containing 
GF per cent. As will be seen, the extraordinary similarity between the structures 
of the iron-carbon and iron-nickel alloys above described would follow as a natural 
consequence of this hypothesis. Hence the way in which taenite is distributed 
relatively to the kamacite strongly supports the view that taenite is a eutectic. 
§ 12. The microscopic characteristics of taenite, when examined under high 
magnification, are in accord with this view. All observers agree that it is not 
homogeneous {of. Tschermak, ‘ Denkschr. Akad. Wiss. Wien/ vol. 31, p. 187, 1871 ; 
Osmond, ‘ Comptes Rendus/ vol. 137, p. 1057, 1903). 
§ 13. The chemical analyses of taenite confirm the view that it is not homogeneous. 
Different analyses of the kamacite of octahedral iron do not vary much among them¬ 
selves and show that this alloy usually contains between 6 and 7 per cent, of nickel. 
It is otherwise in the case of taenite. References are given by Cohen ( loc . cit ., I., 
p. 102, IT., p. 217) to the published analyses of taenite and 1 have arranged these in 
three groups in the following table. 
Percentage 
of 
Ni (Co). 
Meteorite. 
Observer. 
f13-56 
Cosby Creek 
Reichenbach 
14-0 
Caille 
Meunier 
A 15-0 
Caille 
Meunier 
16-68 
Casas Grandes 
Tassin 
19-6 
Kenton 
Nichols 
(24-65 
Welland 
Davison 
26-70 
Welland 
Davison 
25-73 
Staunton 
Cohen and Weinschenk 
27-0 
Cosby Creek 
L. Smith 
28-41 
Magura 
Weinschenk 
29-74 
Cranbourne 
Flight 
[30-33 
Misteca 
Cohen 
[31-54 
Canon Diablo 
Florence 
34-00 
Medwedewa 
Berzelius* 
34-46 
Wichita 
Cohen and Weinschenk 
34-61 
Chupaderos 
Manteuffel 
34-74 
Toluca 
Cohen and Weinschenk 
35-66 
Canon Diablo 
Fahrenhorst 
36-96 
Glorieta 
Cohen and Weinschenk 
37-31 
Bischtiibe 
Cohen 
38-13 
Youndegin 
Fletcher 
48-43 
Beaconsfield 
Sjostrom 
Reference. 
‘Pogg. Ann.,’ 1861, vol. 114, p. 258. 
‘Ann. Chim. et Phys.,’ 1869 (4), 17, p. 31. 
‘Ann. Chim. et Phys.,’ 1869 (4), 17, p. 32. 
‘ Proc. U.S. Nat. Mus.,’ 1902, 25, p. 73. 
‘Field Columb. Mus.,’ 1902, p. 314. 
‘ Amer. Journ. Sci.,’ 1891 (3), 42, p. 64. 
‘ Amer. Journ. Sci.,’ 1891 (3), 42, p. 64. 
‘Ann. Nat. Hofni. Wien,’ 1891, vol. 6, p. 146. 
‘Comp, rend.,’ 1881, vol. 92, p. 843. 
‘Ann. Nat. Hofm. Wien,’ 1889, vol. 4, p. 97. 
‘Phil. Trans.,’ 1882, p. 888. 
‘Ann. Nat. Hofm. Wien,’ 1892, vol. 7, p. 152. 
‘Amer. Journ. Sci.,’ 1895 (3), 49, p. 101. 
‘Pogg. Ann.,’ 1834, vol. 33, p. 133. 
‘ Ann. Nat. Hofm. Wien,’ 1891, vol. 6, p. 155. 
‘ Ann. Nat. Hofm. Wien,’ 1892, vol. 7, p. 150. 
‘Ann. Nat. Hofm. Wien,’ 1891, vol. 6, p. 137. 
‘ Ann. Nat. Hofm. Wien,’ 1900, vol. 15, p. 376. 
‘Ann. Nat. Hofm. Wien,’ 1891, vol. 6, p. 157. 
‘Ann. Nat. Hofm. Wien,’ 1897, vol. 12, p. 54. 
‘ Mineral. Mag.,’ 1899, 12, p. 174. 
‘Sitzungsb. Akad. Berlin,’ 1897, p. 1041. 
