OBSERVATIONS IN CHEMISTRY AND MIN RALOGY. 421 



at the one the sandstone carries essentially carnotite, at the other it carries 

 roscoelite with only a trace of carnotite. Fleck was working with the carnotite 

 variety. Carnotite is a potassium uranyl vanadate; sulfurdioxyd being a deoxi- 

 dizing agent reduces the vanadic radical to vanadyl, becomes itaelf sulfuric ac 1 

 and this latter then forms potassium-uranyl-vanadyl sulfates. This i| quit. 

 rational. But with roscoelite it is different. This mineral is i j>otassium- 

 aluminum-vanadyl silicate. How should a weak acid such as sulfurous acid 

 decompose it, when sulfuric acid of 20 per cent concentration requires a temper- 

 ature of 200° C. and a pressure of 20 atmospheres to effect the decomi>ositioii? 

 Chemistry, however, is not yet an exact science: one cannot foretell absoluteh 

 what will happen from certain given premises. With this in mind the exjn ri- 

 ment was made and the expectation was negatived. 



I. 100 c.c. of distilled water, standing in a glass-cylinder in snow w<r- 



saturated with sulfurdioxyd, meaning that the gas passed into the water 



the bubbles rose without loss of volume. The gas was generated by sulfurio 

 acid from sodium bisulfite; also the gas was fresh from spray by filtering it t h rough 

 4 inches of cotton, and 2 inches of water. The roscoelite ore contains roughly 

 83.5 per cent of quartz grains; 11.0 per cent of roscoelite and 5.5 per cent of 

 dolomite. 1.0 gram of this ore was transferred to glass-tube with 60 c.c of the 

 sulfurous liquid, filling two-thirds of the tube. There was a strong effen nee 

 from carbon dioxyd escaping. A perfect sealing of the tube in t he blast -lamp was 

 obtained after the tube had been sitting in the snow outside at a temperature of 

 minus 16° C. until the liquid was frozen. The object was, in charging as stated, 

 to give the sulfurdioxyd an overwhelming mass and therefore the 1>< st chances of 

 winning the fight. The tube went into the air-bath at 9.20 A. M. At 10 A. M 

 the temperature had become steady at 205° C. ; the action was kept up until 6 P. M 

 At times the temperature rose to 213° C. owing to lessened gas consumed in the 

 laboratories. Since lamp-light interferes with the colors the tube was not exam- 

 ined until 9 o'clock the following morning. The liquid showed a pak-blm color 

 The residue showed dark colored sand, specks of bright yellow substance (possibl: 

 uranyl sulfite?) and large, shiny, globular, solidified drops of sulfur. Of this 

 latter element 0.382 gram was recovered; a part of sulfur was lost by evaporation 

 with hydrofluoric acid and sulfuric acids. The liquid extract yielded 2.52 per 

 cent V 2 6 . Since the total in the ore was 3.43 V A it followed that the efficiency 

 of extraction had been about 73 per cent. But the work was not done by SO,, for 

 the metals were in the filtrate entirely as sulfates, the sulfur dioxyd had merely 

 furnished the materials. The action must have been in line of the I heme 

 3SO, - 2SO, + S. SO, oxidized itself by throwing out sulfur, a very unlooked- 

 for result. 



II. Two grams of ore were sealed up with 50 c.c. of saturated sulfur dioxyd 

 solution (1 c.c. of the solution requires 17.1 c.c. permanganate). Action in bath, 

 \y 2 hours. Temperature average 147° C maximum 164° C. Fxamination on 

 the following morning disclosed that no visible action had taken place. Tube 



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