CONTRIBUTION TO STUDY OF HYDROXYLAMINE. — MACKAY. 329 



New solutions were made up each day as there was evidence 

 of slight decomposition on standino-. 



The water used was purified according to Hulett's^ method. 

 5cc. of sulphuric acid and 5cc. of a saturated solution of potas- 

 sium dichromate per liter of water were added to ordinary 

 distilled water in a large flask with a block tin condenser thrust 

 into the neck and held there by means of a cork made of a 

 mixture of asbestos and plaster of Paris. The water thus 

 obtained wa.s redistilled after addition of a small quantity of 

 barium hydroxide. The water finally received had a mean 

 conductivity of 1.6 x 10'^ expressed in Kohlrausch's new unit.^ 

 The best Avater obtained had a conductivity of 1.05 x 10"'^ and 

 was used for the more dilute solutions. The conductivities 

 obtained were corrected by substracting the conductivity of the 

 water. 



Measurement of Conductivity. 



Conductivity was determined by Kohlrausch's method with 

 alternating current and telephone. A bridge of Kohlrausch 

 pattern, with four resistances, of 1000, 100, 10 and 1 true ohms 

 was used, and wire of resistance 1.4 ohms wound on a marble 

 drum. Both wire and coils were certified by the maker, Queen 

 & Co., of Philadelphia, to be accurate to within .01% and .02^ 

 respectively at 17.5^, and to have a temperature co-efficient of 

 .000267 per ohm per degree centigrade. 



The bridge wire was calibrated according to Strouhal and 

 Barus^ with ten german silver wires of approximately equal 

 length, soldered to stout pieces of copper wire. 



The induction coil was of the form recommended by Ostwald, 

 and was kept in an adjoining room so that the noise of the 

 interrupter would not affect the ear. 



As pointed out by W. H. Ross*, solutions of hydroxylamine 

 and its salts are decompo^ed by platinum electrodes. It was 



1. Zt-chr physik. Chem , 21, 297 (1896) and J. Phys. Chem. I., 91 (1896). 



2. Kohlrausch u. Holborn ; Leitvermogen der Elektrolyte, 1898. 



3. Wied. Ann , 10, 326, (1880). 



4. Loc. cit. 



