in the Periodic Series of the Elements. 113 



W. Preyer. I have adopted Prof. Meyer's device of lettering 

 the sub-groups, adding groups b and c, as in the preceding 

 article. The values are from Landoit and Bornstein, Phys.- 

 Chemische Tabellen, or more recent determinations. 



Group I. C. D. CD. Authorities. 



Lithium 094 0*59 0*555 Eegnault, Bunsen. 



Sodium -283 *97 '274 Schiitz, Gay-Lussac and Tbenard. 



Potassium ... -166 -87 "144 „ „ „ , 



Group I. a. 



Copper 0-0924 8*94 0-826 Naccari, various. 



Silver '0549 1053 '578 Naccari, Eose. 



Gold -0316 19-33 '600 Violle, Eose. 



Group II. 



Beryllium... 0424 1'85 0"784 Nilson and Pettersson, Humpidge. 



Magnesium .. '245 1*74 -426 Kopp, Lorenz ; Bunsen. 



Calcium -1804 157 -283 Bunsen, Mattbiessen. 



Strontium 2*54 Quoted from F. W. Clarke. 



Barium 388 „ „ „ „ 



Group II. a. 



Zinc 0-0915 7'10 0*650 Naccari, Banunelsberg. 



Cadmium ... *055 855 *470 Lorenz, Naccari ; Schroder. 



Mercury -0331 13*596 *448 Winkelmann, Eegnault. 



Group II. b. 



Iron 0*109 7*86 0857 Naccari, various. 



Eutheuium .. *061 12-63 *769 Bunsen, Joly. 



Osmium '031 22-48 *696 Eegnault, Deville. 



Group III. 



Boron 0*251 2*5 ? 0*627 Mixter and Dana , Hampe. 



Aluminium... '212 26 *551 Eegnault, Naccari; Deville, Heeren, 



Mallet. 



Gallium -079 595 *470 Berthelot, Boisbaudran. 



Indium -0569 7"42 *422 Bunsen, Winkler. 



Thallium ... *0335 11-85 '397 Eegnault, de la Eive. 



Group III. a. 

 Scandium ... 



Yttrium 



Lanthanum .. 0*0448 6*1 0*273 Hillebrand and Norton. 



Group IV. 



Carbon 1 Q.904 3-158 0-644 ( Bettendorff and Wiillner, v. Baum- 



(diamond). J [ hauer. 



Silicon (cryst.) *177 239 *411 Eegnault, Winkler. 



Germanium .. *073 5'469 *399 Nilson and Pettersson, Winkler. 



Tin -054 7-29 *393 Schiitz, Lorenz ; Matthiessen. 



Lead ... ;030 11*352 *340 Eegnault, Lorenz ; Eeich. 



Group IV. a. 



Titanium ... 0-1125 Nilson and Pettersson. 



Zirconium ... *066 415 0274 Mixter and Dana, Troost. 



Cerium *0448 665 *298 Hillebrand and Norton. 



Thorium *0276 11*0 -303 Nilson. 



PhiL Mag. S. 5. Vol. 39. No. 236. Jan. 1895. I 



