Chemistry and Physics. 65 



until heat is applied. As to its conductivity for heat, experiments 

 are described which show that at high vacua water gas is a better 

 conductor than either air or hydrogen at similar pressures. " It 

 has been found," he says, "that as water gas is rarefied, its heat 

 conductivity diminishes in a greater ratio than that of hydrogen." 

 " At these high vacua water gas gains so rapidly on hydrogen 

 that I am prepared to believe that at Mr. Brush's low pressure of 

 0*38 millionth, the ratio may even be as great as that he ascribes 

 to etherion." "On the evidence at present available," he con- 

 cludes, " I consider it more probable that aetherion is water vapor 

 than that it is a new elementary gas." — Chemical Neios, lxxviii r 

 221, November, 1898. g. f. b. 



3. On the Preparation of Graphitic Acid. — An easy method 

 of preparing graphitic acid has been described by Staudenmaiek. 

 A mixture is first made of 100 cc of concentrated nitric acid (sp. 

 gr. 1*4) and 300 cc of ordinary strong sulphuric acid. To this are 

 added 50 grams of pulverized Ceylon graphite, and then 100 

 grams of potassium chlorate, in small portions at a time ; the 

 whole being frequently stirred. After the mixture has stood for 

 several hours, it is poured into water, and the solid is washed, 

 dried and ignited in a large dish of metal until it has intumesced. 

 Then it is again stirred with water, and the portion that floats is 

 collected for use in the subsequent operations. Of this prepared 

 graphite, 25 grams are poured, with constant stirring, into a cold 

 mixture of one liter of strong sulphuric acid and half a liter of 

 strong nitric acid contained in a shallow dish, and then about 450 

 grams of potassium chlorate are added in successive portions. 

 After the active evolution of gas diminishes, and a sample of the 

 resulting green substance appears pure yellow on treating it 

 with acid permanganate, the whole is poured into water, and the 

 resulting solid is washed repeatedly by decantation. It is now 

 placed in a dish and a solution is added to it consisting of seven 

 grams of potassium permanganate dissolved in 120 cc of hot water; 

 after cooling, a mixture of 15 cc of strong sulphuric acid with 1o cc 

 of water is added, and the whole is heated on the water bath 

 until the red color has disappeared. Hydrogen peroxide is 

 added, the whole is allowed to stand at rest for some time with 

 occasional stirring, and the graphitic acid is then washed first 

 with dilute nitric acid and finally with alcohol and ether. — Per. 

 Perl. Chem. G-es., xxxi, 1481-7, June, 1898. g. f. b. 



4. On Compounds of Lithium and Calcium with Ammonium. 

 — The fact has been observed by Moissan that when liquefied 

 ammonia, contained in a tube cooled to — 50°, is brought in con- 

 tact with metallic calcium or lithium, solution takes place with 

 the production of an intense blue liquid having a brown red 

 reflection ; this result being comparable to the similar phenome- 

 non observed with potassium and sodium. These latter metallic 

 ammoniums when thus produced, according to Joannis, have the 

 formulas KNH 3 and NaNH 3 , and they decompose at the ordinary 

 temperature and pressure, evolving ammonia gas and regenerating 



Am. Jour. Sci. —Fourth Series, Vol. VII, No. 37.— January, 1899. 

 5 



