CUCI A gC1 AuCI elle' A gC1 AuCl Cuprous chloride. Aruntic chloride. Aurous chloride.

But it has been pointed out that certain of the silver compounds are isomorphous with the corresponding sodium and potassium compounds, and as there is no reason to suppose that the argentic compounds generally are not of similar constitution to argentic chloride, the conclusion that there are two atoms of silver in the molecule of argentie chloride would appear to necessitate the assumption that the compounds of the alkali metals also contain at least two atoms of the metal in their molecules ;-that the formula of sodium nitrate, for example, is Na2(NO3)2, and not NaNO3. The existence of a compound of sodium ethyl with zinc ethyl, NaZn(C,II,),, from which the former cannot even be separated, appears to show that sodium does not invariably function as a monad.

Speculations of this kind are extremely hazardous, but, as no method is known enabling us to ascertain the molecular composition of compounds which cannot be volatilized, they possess a certain interest and, moreover, point to the necessity of investigation in this direction.

U Eli ENIUM-R 110DIUM-PALLADI UM-OSMI UMIRIDIUM-PLATIN U Symbol. At. wt.

Ruthenium ■ - ■ tp co co c••• co co oo co a, Palladium These metals always occur in the native state, and are usually associated together. The relation between Reaction.

Din, Cl2 111,990 , 94,770 116,280 Mn„ 08, K2 389,650 A1nCl„ Aq 16,010 lInSO4+ 41-120 , Aq 1,770 A111804+51120 , Aq -20,790 .Aln(OH)„ SO3Aq 26,4S0 Mn(OH)2, 21-ICIAq 22,950 Mn , 0 , SO3Aq 121,250 AI n , C12, Aq 125,000 2Aln(01I)„ 02, 2KOHAq 14,760 2A.In0(011)2, 05, 2KOHAq - 28,260 Reaction.

Fe , C12 82,050 Fee , CI6 192,060 2FeCl„ Cl, 27,960 Fe, 0 , H20 68,2S0 Fe2, 0„ 31-120 191,130 2Fe(OH)2, 54,570 Feel, , Aq 17,900