CHEMISTRY. 297 



acid of the formula C6H4\'op^ tt ^ ^' While the evidence in 



favor of the formula given above for the product obtained from the 

 high-melting chloride is not as clear as we should Uke, there is little 

 room for doubt that the formula is correct. On the other hand, the 

 e\'idence in favor of the formula of the product from the low-melting 

 chloride is conclusive. It therefore appears that the conclusion drawn 

 from the earlier experiments is wrong and that, as a matter of fact, it 

 is highly probable that the high-melting chloride is the unsymmetrical 



one represented by the formula, C6H4<' on^/C), and that the lowr 



\ feU2/ yQQQl 



melting chloride is the symmetrical one, C6H4<(' ^>^ ^,. The work 



of Dr. Hopkins all pointed to this as the correct conclusion. The 

 details will be published later. 



Next the investigation was taken up by Dr. J. H. Sachs, and his 

 work was carried on during the academic year 1916-17. He studied 

 the action of anisol and of phenol on the two chlorides in the presence 

 of aluminium chloride in solution in carbon bisulphide. 



With anisol the high-melting chloride gives the dimethylether 



C(C6H40CH3)2 



of sulphonphthalein, C6H4\ >0 , while the low-melt- 



ing chloride gives the sulphon-chloride represented by the formula, 

 C6H4"\' ^^ "p," * ^. These results again point to the formula 



C6H4<^^^^^")>0 for the high-melting chloride, and to C6H4<^^^ p, 



for the low-melting chloride. 



When phenol and aluminium chloride are allowed to act upon the 

 high-melting chloride in solution in carbon bisulphide two products are 



C(OC6H5)2 



obtained. One of these is the compound C6H4<^ >0 , the other 



^S02 



C(C6H40H)2 



is phenolsulphonphthalein, C6H4<(' >0 . The formation of 



\S02 



both these compounds is in accordance mth the view that the high 



,CCl2 



melting chloride has the unsymmetrical structure C6H4<r > . 



^S02 



But now comes another one of those troublesome contradictions that 

 made it so difficult in my earlier investigations to draw conclusions. 

 The low-melting chloride, when treated with phenol and aluminium 

 chloride in solution in carbon bisulphide, gives exactly the same prod- 

 ucts as the high-melting chloride! 



