86 



L. F. Nilson, 



When dried at 100°, the salt has parted with 5 mol. of water out 

 of 7 (calc. 14.53), and the residue is consequently identical with that, 

 which under the same circumstances was obtained from the preceding 

 neutral salt. 



4. "A-Seleilite: Fe 2 .0 G .3SeO + H 2 .0 2 .SeO + 7H 2 0. 



By digesting the basic salt, mentioned under 1, with that quantity 

 of acid which was required, in order that a diselenite might be formed or 

 59.3 pr. ct. selenious anhydride, there was obtained, after evaporation of 

 the solution at a gentle heat, a greenish-white, crystalline salt. It is so 

 insoluble in water that sulphocyanate of potassium does not cause any 

 colouring, but the liquid assumed sour reaction. 



Analyses: 



1) 0.541 gr. salt gave 0.2267 gr. selenium or 0.3185 gr. selenious acid 

 and 0.H55 gr. oxide of iron. 



2) 0.4685 gr. salt gave 0.1955 gr. selenium or 0.2747 gr. selenious acid 

 and 0.104 gr. oxide of iron. 



3) 0.3132 gr. salt, when heated to 100°, gave off 0.0247 gr. water. 



Represented in 100 parts: 



found calculated 



1. 2. 3. 



Oxide of iron .... 21.35 22.20 — Fe 2 3 160 21.39 



Selenious acid .... 58.87 58.63 — 4Se0 2 444 59.36 



Water (loss) 19.78 19.17 7.88 8LTO 144 19.25 



100.00 100.00 748 100.00 



On drying at 100°, this compound seems to give off 3 mol. of water 

 out of 8 (calc. 7.22). With another amount of water this salt 



5. Vs-Selenite: Fe 2 .0 6 .3SeO + H 2 .0 2 .SeO + 9H 2 0. 



was obtained by treating the basic salt with so much anhydride, that a 

 tetraselenite could have been formed or 166 pr. ct. its own weight. The 

 compound, thus obtained under the same circumstances as the preceding 

 salt, exhibited also a similar appearance and the same properties. 



