1830.] On the Limits of Vaporization. 211 



minute crystals of the substance were even attached to the 

 under part of the stopper in the bottle. Hence corrosive 

 sublimate is volatile at common temperatures. 



No. 12 and 13. Bottles, solution of chromate of potash; 

 tubes, in one, chloride of lead in powder, in the other nitrate 

 of lead in crystals. In both these experiments the chromate of 

 potash had acted upon the lead of the glass, and rendered it 

 yellow and dim ; so that no indication could be gathered re- 

 lating to the volatility of the compounds of lead. 



No. 14. Bottle, solution of iodide of potassium ; tube, chloride 

 of lead. Both remained unaltered ; the solution of iodide was 

 perfectly clear and colourless ; no trace of the chloride of lead 

 had passed over in vapour. 



No. 15. Bottle, solution of muriate of lime; tube, crystals of 

 carbonate of soda. A part of the water has passed to the car- 

 bonate of soda ; but both it and the remaining solution of mu- 

 riate of lime are perfectly clear. No portion of either salt has 

 volatilized from one place to another. 



No. 16. Bottle, dilute sulphuric acid ; tube, nitrate of am- 

 monia in fragments. The nitrate was slightly moist. The 

 acid being examined was found to contain nitric acid, whilst the 

 test acid, No. 7, was perfectly free from it. It would therefore 

 appear that nitrate of ammonia is a salt volatile at common 

 temperatures ; although it is just possible that slow decom- 

 position may take place in it, and so nitric acid or its elements 

 pass over. , 



No. 17. Bottle, solution of persulphate of copper; tube, 

 crystals of ferro-prussiate of potash. The crystals had attracted 

 most of the water from the cupreous salt ; but the solution of 

 ferro-prussiate and that of the copper had their proper colour; 

 neither were rendered brown ; no salts had been volatilized. 



No. 18. Bottle, solution of acetate of lead; tube, iodide of 

 potassium. The acetate of lead is now dry ; the iodide of 

 potassium has taken all the water and formed a brown solution, 

 in which there is free iodine ; probably a little acetic acid has 

 passed over and caused the change in the iodide of potassium. 

 There is no appearance of iodide of lead in the tube, but there 

 is in the bottle, and most probably in consequence of the vapo- 

 rization of the free iodine from the solution in the tube. 



From these experiments it would appear that there is no 



