PROXIMATE PRINCIPLES OF SOME OF THE LICHENS. 
83 
Calculated numbers. 
I. 
18 C 
1375*8300 
40*82 
41*11 
11 H 
137*2745 
4*07 
4*28 
BaO 
956*8800 
28*36 
28*20 
9 0 
900*0000 
26*75 
26*41 
3369*9845 
100*00 
100*00 
These numbers give C^g Hg 07-{-Ba0+2 aq=eyem. BaO+2 Aq. 
I. 0*168 grm. salt dried four days in vacuo, gave 0*0635 BaO C02 =0*0492 BaO 
= 29*28 per cent. BaO. 
II. 0*1525 grin, salt dried four days in vacuo, gave 0*0577 BaO C02 =0*0447 BaO 
=29*31 per cent. BaO. 
0*2091 grm. salt with chromate of lead gave 0*323 carbonic acid and 0*080 water. 
Calculated numbers. 
Found. 
C 18 
1375*8300 
42*23 
I. 
42*12 
11. 
H 10 
124*7900 
3*83 
4*24 
BaO 
956*8800 
29*37 
29*28 
29*31 
8 0 
800*0000 
24*57 
24*36 
3257*5000 
100*00 
100*00 
These numbers give Cjg Hg Oy-j- BaO+Aq for the rational formula of this salt of 
baryta = evern. BaO+Aq. 
0*298 grm. same salt dried at 212°, gave 0*137 BaO S03 =0*0899 BaO =30*16 per 
cent. BaO. 
0*261 1 grm. salt, also dried at 212° Fahr., gave 0*413 carbonic acid and 0*092 water. 
Calculated numbers. 
Found. 
18 C 
1375*8300 
43*74 
43*13 
9 H 
1 12*3155 
3*57 
3*91 
1 BaO 
956*8800 
30*42 
30*16 
7 0 
100*0000 
22*26 
22*80 
3145*0255 
100*00 
100*00 
The formula of this salt, which appears to be anhydrous, is C^g Hg 07+BaO = eyeAv?. 
+ BaO. 
It is evident from these results that evernesate of baryta exists in three states, viz. 
as an anhydrous salt, and with one and two atoms of water. 
The Silver Salt. 
The silver salt was formed by precipitating a neutral solution of evernesiate of 
ammonia with nitrate of silver ; it is a white precipitate. 
1. 0*247 grm. salt gave 0*092 silver =0*0988 AgO = 40*00 per cent, oxide. 
II. 0*141 grm. salt gave 0*053 silver =0*0569 AgO=40*35 per cent, oxide. 
0*3835 grm. salt gave 0*522 carbonic acid and 0*1113 water. 
