The residue is washed, extracted by dilute hydrochloric acid, and again well washed with boiling water.
Transparent soaps are prepared by dissolving ordinary soap in strong alcohol and distilling off the greater portion of the alcohol till the residue comes to the condition of a thick transparent jelly.
There was, therefore, a residue of 9% of illiterates, most of whom were not born in Australia.
A heavy white precipitate, consisting of ammonium chloride and columbium nitride, is thrown down, and the ammonium chloride is removed by washing it out with hot water, when the columbium nitride remains as an amorphous residue (Hall and Smith, loc. cit.).