44 



iooIrCl.,N,H.Cn , „ 



conl.in } 44-3691 Pt 



43732 ,, Seubert 



ioohCUsXl ) 

 contain ( 



39-SS „ 29-291 



NA TURE 



{Nov. 13, 1884 



40-3S74 » ; 28-8097 Cl; 30-803 KC1 



29 



3082 ,, Seubert 

 Berzelius 



The same discrepancies as in the case of the platinum salts 

 present themselves : as the percentage of the potassium chloride 

 is exact , that of IrCl 2 follows ; and, as to the weight of the chlorine, 

 the difference of the percentages found by the two experimenters 

 shows that there is the same cause of error as in the correspond- 

 ing platinum salt. 



iooPdCl,.2KX'l 

 contain 



32-678 Pd ; 21-4512 CI ; 458708 KC1 



32-69 ,, 21-416 „ 45-892 „ Berzelius 



The agreement is here as good as complete ; but the values 

 actually derived from these data vary from Pd = 104-674 to 

 1 10-796, owing to the value of the weight assumed for chlorine. 



100Rh.Na3Cl3.CJ3 contain— 



27-1468 Rh; 45-6215 NaCl ; 27-2317 Cl 



27 - 094 „ 45-577 „ 27-329 ,, Berzelius 



100Rh.2KCl.Cl3 contain— 



29/1276 Rh; 541 -6537 KC1; 29-2187 CI 



28-989 „ 41-45 „ 2Q . 56l ;| Berzelius 



The agreement is almost complete in the case of the sodium salt 

 and not doubtful in the other, because the weight of KC1 is 

 certain. The values for rhodium derived from the sodium salt 

 are very discordant, varying from 102-98 to 105-696. 



•100Ru.2KCl.CI3 ) „ „ ■ 



contain J 28-9984 Ru; 41-7297 KC1 ; 29-2719 Cl 



Numbers actu- j „ .. 



•28-96 „ 4I - 39 „ ,j 



ally found 

 Mean of the 3 

 experiments 



2S7S 



41-09 



jO-17 



The calculated amount of ruthenium is undoubtedly the actual 

 percentage, because 28-91 Ru were found in the second experi- 

 ment as 28-96 m the first; and the weight of KC1 not being 

 doubtful, that of chlorine can only be as calculated. The results 

 which have been derived from these data are most discordant, 

 viz. Ru 96-854 — 107-19. 



The weights of column s give 6 = 16 and S 3 = 16 ; those of 

 column?, 6 = 15-319,4, S 3 = , 5 . . . . There is consequently 

 a difference of the chemical proportions in the two states which 

 explains many anomalies encountered in analytical work and 

 among other, the following :— Berzelius observes (Pogg inn 

 yin. p. 16) that, from causes which he has been unable to discover, 

 the atomic weight of sulphur cannot be derived from the specific 

 gravities of the gaseous compounds H 2 S and SO.,, the numbers 

 obtained being so high that the discrepancies exceed the limits 

 of possible errors of observation. He had obtained S = 201 -165 

 from the analysis of PbSO, ; Thenard and Gay-Lussac's weigh- 

 ing of H a S gave S = 203-9 ! his own weighing of SO,, 207-58. 

 His weight for O being ,00, these 207-58 S represent 407*58 

 SO a , which with S :! = O i; give S = 20379, practically the 

 same as the value derived from the other gaseous compound. 

 The two numbers 203-9 and 203-79 reduced to the value of the 

 weights of column /give respectively 191-056 and 191-053. 

 Berzelius s number 201-165 corresponds to the value of column /, 

 fj, l'" g ~ru ' , Wlth H = °"95745- the actual weight, it becomes 

 19- &05. he three numbers in hydrogen units— 15-292, 15-284, 

 and i5- 4 o8-though from different causes all too large, a-ree 

 with each other as well as can be expected under th! circum- 

 stances, and the difficulty disappears therefore with the adoption 

 of the weights of columns s and / for the two different states. 

 w„-il'i -n g ,°' v ' S ■?, , be ex P ect «l that for other states the 

 weights will also be still further different, and this conclusion is 

 fully confirmed by the facts. Let the weights of column / be 

 - 1, then the weights nf the states „, i, and c are as follows :- 



a = 0-999104 ; b = 0-997338 ; c = 0-99468. 



Instead of such loss of weight there may be a gain to the same 



extent, as, for instance, in the state - = 1-002662. There are still 



other variations which are multiples of a, b, c, as 



ft 5 = 0-99866 ; — = 0-99424 ; cb — 0-99203. 



The evidence of the reality of these weights appears from the 

 following comparison with some of the very best experiments on 

 record. The numbers marked with an asterisk are derived by 

 the volumetric method, which, in consequence of variation of the 

 atomic weights, yields in all cases more or less faulty results. 



iooKClO., contain . 



Mean of all experi- 

 ments on record 



60-87379 KC1 = , 



60-81927 ,, = <7 



iooAg = c yield .. 

 Mean of all experi 



ments on record j 

 iooAg correspond to 



iooAg yield 

 iooAgCl yield 



60-84653 



60846 



132-8426 AgCl 

 i32-S 4 iS 



Berzelius, Penny, Pelouze, 

 Marignac, Gerhardt, 

 Maumene, Stas 



[ Berzelius.Turner, Penny, 

 <. Marignac, Maumene, 

 ( Dumas, Stas 

 69-0244 KC1 = a 

 \ 69-062 ,, Marignac 

 I 69 10345 » Stas " 

 "4-S733 AgS = <A 

 114-8581 ,, Dumas, Stas, Cooke 

 86-4733 ., = <A 

 ?,(t-An^^ S Berzelius, Svanberg, and 



t/oj >> j Struve 

 iooAg correspond to 54-1258 NaCl 



•54-2076 „ Pelouze, Dumas, Stas 



iooAg yield W4707 AgN 3 O c = b 



Mean of 7 experi- | 



ments j" I 57'472 ■■ s ' is 



Mean of all experi- ) 

 ments on record / " ^'^ 

 looAgN.jO^ corre- 

 spon! to 



iooAgN 3 O i; corre- 

 spond to 



100KCI = a yield ... 



Penny, Marignac, Stas 



84-3?994 AgCl 



84-3743 >> Turner, Penny 



43-S33I KCl = o 



'43-8715 .. Marignac, Stas 



I35-6532 KN. t O s = c 



1356423 ,, Stas 



'35-6345 >, Penny 

 looKClOs „ ... S2'5o33 ,, 



82-500 ,, Penny 

 iooNaC10 e „ ... 79-8917 NaN 3 6 = — 



79-8823 ,, Penny" 

 iooNaCl ,, ... 145-435 tl — £_? 



I45'4i64 



I45-4526 , 



64-6608 Ag 



64-664 ,, 

 64-6065 ,, 



' ' 59j367 >, 



59-2806 „ ,, lt 



1 I 62-0621 ,, 



62-0016 ,, 

 iooBaCI yield ... 138-0494 AgCl 



'38-07 ,, Berzelius 

 » ,, .. 112-251 BaS0 4 



112-19 ,, Turner 



112-175 ,, Berzelius 

 560312 CaO = 1 

 56-0198 S Dumas. Erdman, and 



iooAgC 4 H 3 4 = c 

 contain 



iooAgC.,H 2 6 

 contain 



iooAgC 4 H 2 5 



contain 



Penny 

 Stas 



Marignac 



Liebig and Redtenbach 



iooCaC0 3 = c yield 



( General mean 

 iooCaC0 3 = c yield 

 iooPb 

 iooPbO 



Marchand 

 136-0037 CaSOj = 1 

 136-0525 ,, Erdman and Marchand 

 146-4418 PbS0 4 



146-4262 ,, Berzelius, Turner, Stas 

 I35-853 

 ■35-804 ,, Turner 



