and Crystalline Condition of Bodies. 261 



KHgO, SOsX , ^, „ „ / 1-626 \^ .„^„„ / 34892 



Ai; Ol 3 S O J + -^ "= O I 1.625 ) ^°PP ^^^^^ [ 3491 4 



Fe.O^sloO'^^*^-^ 1-712 Kopp 60097 3510-2 



Cr^o'iSh)^^^^-^ 1-848 Kopp 6295 8 3406-8 



The crystallized double Sulphates of Potash or Ammo7iia and 

 Magnesia, Copper, Iron, Manganese, Cobalt, Zinc, Cadmium 

 or Nickel. 



1314-7 

 13340 



MgO.SOg \ g„ Q / 1-721 Thomson » ooqc. ( 

 NoHgO, 8 03^+''"- (1-696 Gmelin / ~"'''~ ^ \ 



^"J^'g q"3 V 6 Ho O 2137 Kopp 2762-8 1292-8 



CuO, SO3 \,^„ ^ / 1-757 \,.„„ oiQQ.o / 1422-8 



N,H36,S03;+^"^^ 1 1-756 )^^°PP ^^^9^ 1 1423-7 



nYi"o so') "^*'"'° 1-930 Thomson 2450-1 1269-2 



1?0 's o' ) + 6 H. O 2153 Kopp 2770-4 12868 



NiO, S0\ , fiH O ^^■^l^^ Knnn o-j-xa-n / 1296-4 



KO.SOjy +6H„0 ^g.jgg^Kopp 27368 | joj^j.g 



C 1-801 Thomson -. f 1373-6 



NiO.SOaX g„o 11-783 I ojyQ.q J 13874 



N.HsO.SOa^ +^"- il-9I5)Kopp ^-^739 ^ jog^.g 



ll-92K J L 1287-8 



Apatite, Green afid Broion Lead Ore. 



r3-15 \^ ■] f 2184-1 



CaCl,+3(Ca3 03,P2 0,)p-25 y^^"""'''"" I 6879-8 J 2116-9 



L 3-225 Mohs J L 2133-3 



PbCI,+3{Pb.O>,RO.){^:»,„ ^--°" } 1C964-6 {IJf^l 



P1,OI,+3(P1„0.,A,,0,,{5:|„, Nn.,,n„n j ,3,„„ jg84.5 



By reference to the table now given, it will be seen that our 

 law has received ample confirmation ; but it still remains to 

 be explained why the atomic volume in several of the isomor- 

 phous groups is not absolutely equal. 



The law can obviously hold only for those bodies which 

 are perfectly isomorphous. But this is seldom the case, for 

 those bodies termed isomorphous are generally only approxi- 

 mately so, for we find the angles of their cr\'stals deviatinf>- 

 several degrees from one another j neither are the relations 

 between the axes of bodies thus denominated isomorphous 

 perfectly equal. But it is evident, that the more nearly the 



