152 Scientific Intelligence. 



tion of water gas and have now studied the reaction which takes 

 place at high temperatures between the vapor of water and car- 

 bon monoxide. The gases were passed through a glass tube con- 

 taining a layer of pumice-fragments 80 cm. long. The carbon 

 monoxide prepared from potassium ferrocyanide and sulphuric 

 acid and purified from oxygen and carbon dioxide by phosphorus 

 and potassium hydrate, passed through water heated to 80° on its 

 way to the tube ; thus giving a mixture of about equal mole- 

 cules. The tube was heated in a combustion furnace, the temper- 

 ature being determined by means of the melting of salts of known 

 fusing points. In the first experiment, in which the temperature 

 lay between the fusing point of silver iodide (530°) and pyrophos- 

 phate (585°) the evolved gas contained no carbon dioxide and 

 after explosion with oxygen no indication of the presence of 

 hydrogen; a result confirmed by a second experiment. In the 

 third experiment, the temperature was carried to between 602° 

 and 634°, and the evolved gas contained 1*5 per cent carbon 

 dioxide and 3 per cent hydrogen. For higher temperatures, por- 

 celain tubes were used 8 mm. diameter, heated in a Fletcher 

 furnace. The carbon monoxide, carefully freed from the dioxide 

 and oxygen was mixed with water vapor and in the fourth exper- 

 iment passed into the tube, heated in the furnace to between 861° 

 and 854°. On analyzing the issuing gas, 8 per cent of carbon 

 dioxide was found present. In the fifth experiment, the tube was 

 filled with pumice for a length of 25 cm. The gas evolved con- 

 tained 10 - 6 per cent carbon dioxide. Since the silver spiral 

 placed in the tube had melted and the copper spiral had not, the 

 temperature reached must have been 954°. Hence it appears 

 that no apparent reaction takes place between carbon monoxide 

 and water vapor at 560° ; that at 600° about 2 per cent, at 900° 

 8 per cent, and at 954° about 10*5 per cent of the monoxide is 

 converted into dioxide. Thus the very conditions which oppose 

 the action of hydrogen upon carbon dioxide, favor the action of 

 water vapor upon carbon monoxide. — Ber. JBerl. Chem. Ges., 

 xviii, 2894, Nov. 1885. G. F. b. 



6. On the Atomic weight of Cerium. — Beauner has made an 

 elaborate investigation of the cerium group of metals and now 

 gives the results of his determinations of the atomic weight of 

 cerium. For this purpose anhydrous cerous sulphate was em- 

 ployed, the atomic weight being calculated from the eerie oxide 

 which this salt left on ignition. For the preparation of the sul- 

 phate, the crude oxides obtained from cerite were dissolved in 

 nitric acid, the excess of acid removed by evaporation, the syrupy 

 liquid slightly diluted and poured into a large quantity of pure 

 boiling water. Almost the whole of the cerium present was pre- 

 cipitated as basic eerie nitrate. After washing this was dissolved 

 in nitric acid and again precipitated with water ; thus obtaining a 

 series of fractions. To obtain the cerous sulphate, the eerie 

 nitrate was dissolved in sulphuric mixed with sulphurous acid; 

 the excess of acid evaporated, the heavy metals precipitated with 



