CUBICAL EXPANSION OF SOLIDS. 



8 



large number of such determinatious have beeu given. Many observers of thermal ex- 

 pansion have determined, not the values of the constants a and b, but the values of the 

 mean coefficient throughout given ranges of temperature. In many cases, especially in 

 cases in which the values of a and b are not known, these results have been given. They 

 are contained in the fourth column, and in the fifth column are stated the temperature 

 ranges to which they apply. In general, also, these temperatures are the ranges 

 throughovit which observations were made. A more complete list of the older determina- 

 tions of mean coefficients of expansion will be found iu Part III of the " Constants of 

 Nature," by Prof F. W. Clarke, published in Vol. XIV of the Smithsonian Miscellaneous 

 Collections, but Prof Clarke's tables do not give the values of the constants a and b. 



Substance. 



Aluminium (cast) 



Do. (commercial). 



Do. 



Do. 



Alums (in powder) — f 

 Ammonium-Alumin- | 



ium Alum -[ 



I 

 I 



r 



Potassium-Aluinin- | 

 ium Alum -J 



I 

 r 



Rubiclium-Alumin- | 

 ium Alum j 



I 

 I 



Csesium-Aluminium j 

 Alum \ 



I 



Potassium-Chrom- 

 ium Alum ] 



I 



Ammonium Sulphate. 



Antimony 



Do. (i)ure) 



a X 10" 



Do. (crystal) . 



6664 



2770 



33S7 



b X 10" 



3435 



3970 



870 



c X 10'^ 



Mean Co- 

 efficient x 10*' 



7008 



6060 



7439-4 



7062 



2840 



2585 



5343 



2635 



4198 



31118 

 2070 

 2035 

 5045 

 2610 

 2621 

 7699 

 2330 

 4968 



59503 

 8335 

 9051 



11191 

 3167 

 2940 



3379 



Temperature 

 Range. 



CC.) 



0—100 

 0—100 

 0—100 

 0—100 

 0— 20 

 0— 60 

 0—100 

 0— 20 

 0— 60 

 0— 90 

 0— 20 

 0— 60 

 0—100 

 0— 20 

 0— 60 

 0—100 

 0— 20 

 0— 60 

 0— 80 

 0— 20 

 0- 60 

 0—100 

 0—100 

 0—100 



0—100 



Obsekveb. 



Fizeau 



Calvert, Johnson & 

 Lowe 



L. Pfaff 



Glatzel 



Spring 



M atth lessen 



Calvert, Johnson & 

 Lowe 



Fizeau 



