903 



of course was done without benzopurpuriii being present in the bath. 



Now, when a dye and a salt are present at the same time, pro- 

 bably more sail will penetrate the tibre; these quantities however 

 were very small, as the ash content of the fibre material after 

 dyeing did not amount to more than 3 milligrams. 



The correction meant above consisted in this, that in the standard 

 solution a quantity of salt was put equal to that of the exhausted 

 dye-bath. It is true, by that the error was not quite avoided, because 

 wnequal layers of the liquids have to be compared ; however, since 



