However, the applicability of the erythrosin method is not limited to the conditions set forth in that procedure. One way of extending the scope of the method is based upon the use of standard solutions that have concentrations other than 0.1 .A few determinations carried out with 0.05 M and 0.2 M lead nitrate showed that with these solutions accurate results can easily be obtained, provided the conditions (quantities of alcohol and indicator) are adjusted adequately.It will be worth while to study the titration with these standards more closely with the purpose of working out analytical procedures for the estimation of amounts of sulfate that are either larger or smaller than those of the above range. Such an extension of the method would also broaden the applicability of the successive determination of chloride and sulfate that has been suggested in this paper. Another fertile field for further investigation is the replacement of ethyl alcohol by diluents that can be obtained without legal restrictions. Preliminary experiments revealed that both acetone and isopropyl alcohol give satisfactory results, though a somewhat smaller volume is to be used for a given titration as compared to ethyl alcohol.