METHOD OF HAIXE EXPERIMENT STATION 



97 



The filtration of the ammonium magnesium phosphate is made 

 through gooches. The asbestos felt is prepared in the following 

 way : The coarse fibers of asbestos are chopped up with a sharp 

 knife on a glass plate and boiled for two hours with strong hydro- 

 chloric acid ; afterwards, by repeated washing with distilled water, 



Fig. 5. Rossler Ignition Furnace. 



they are freed from acid and the fine particles of asbestos which 

 would tend to make the filter too impervious. After the last wash- 

 water is poured off, the asbestos is suspended in water and used 

 for making the felt on the filter. The preparation of the crucible 

 and the filtration under pressure are accomplished in the usual 

 way. 



The ignition of the precipitate is accomplished in a Rossler ig- 



