188 PROCEEDINGS OF THE AMERICAN ACADEMY 



of the two acids. We have also made a dibrommethylpyromucic 

 acid melting at 175°, in which one bromine atom is situated in the 

 furfuran ring, the other in the side-chain. By the action of water 

 upon the two acids which contain halogen in the side-chain we 

 have made the corresponding oxy-acids. 



We had intended to make a thorough study of the higher boiling 

 fractions of the crude furfurol, and to determine as far as possible 

 the nature of the various constituents ; but the investigation of the 

 methylfurfurol and its derivatives proved so much more attractive 

 that we have contented ourselves with the partial examination of 

 the fractions boiling at 200-215° and established in them the pres- 

 ence of guaiacol. 



Methylfurfukol. 



The material which we had at our disposal was that portion of 

 the crude furfurol which remained behind at 175° on distilling the 

 oil several times from ordinary retorts or boiling flasks. It had 

 been accumulating for more than ten years, was dark in color, 

 somewhat thick and viscous, and left on distillation a large tarry 

 residue. We therefore distilled it from small copper retorts until 

 signs of decomposition appeared. While the earlier investigations 

 had shown that the temperature could be pushed to over 300° 

 without essential decomposition, we now found that carbonization 

 ensued at about 250°. At first we ascribed this difference in be- 

 havior to decomposition effected by long standing of the material; 

 but we subsequently learned that changes had also been made in 

 the mean time in the factory methods, and that it was quite possi- 

 ble that the greater part of our material had been subjected to the 

 newer treatment. A special examination of the residue yielded 

 by the distillation of nearly fifty kilograms of a fresh supply of 

 crude furfurol showed that in this case decomposition also set in 

 at 250°, so that no products boiling above this temperature could 

 be obtained. 



On fractioning with the aid of a Hempel column the yellow dis- 

 tillate which was first obtained, we soon found that it still con- 

 tained considerable quantities of furfurol, and, aside from this, that 

 a comparatively large portion distilled between 180° and 185°, 

 and a smaller portion at 200-220°. As the distillation progressed, 

 the intermediate fractions diminished in such a way that it became 

 evident that but one body could be isolated between 165° and 

 200°, and that it boiled at a temperature not far from 185° (un- 



