160 PROCEEDINGS OP THE AMERICAN ACADEMY 



0.8140 grm. substance gave 1.5910 grm. CO2 and 0.2910 grm. H2O. 



The acid prepared in this way melted at 128-129° ; and, since the 

 melting point of pyromucic acid is usually given somewhat higher, it 

 seemed advisable to subject this product to further purification. Mr. 

 J. J. Thomsen, therefore, prepared the ethyl-ether of the acid by satu- 

 rating its solution in absolute alcohol with hydrochloric acid, precipitat- 

 ing with water, and washing first with a dilute solution of sodic 

 carbonate and then with water. He then found that the carefully 

 dried ether distilled from the first drop to the last unchanged at 195° 

 (Mercury column completely in vapor) under a pressure of 766 mm. 

 On cooling, it crystallized in large transparent prisms, which melted at 

 34°. According to Malaguti,* ethyl pyromucate melts at 34°, but boils 

 at 208 - 210°, under a pressure of 756 mm. For the determination 

 of boiling point, we employed about 30 grm. of the ether, and an 

 analysis showed its purity. 



0.5615 grm. of substance gave 1.2330 grm. COo and 0.2940 grm. 



Calculated for C5H3O3C2H5. Found. 



C 60.00 59.8 



H 5.71 5.81 



A portion of this ether was saponified with sodic hydrate, the acid 

 liberated from the sodic salt, recrystallized from hot water several 

 times, and finally melted. The solidified acid melted at 130°, 5 (uucom.), 

 while an acid made directly from mucic acid melted at 130°. The 

 corrected melting points of the two were 133° and 132.°5; whereas 

 Schwanertf gives the corrected melting points 134°. 3 and 132. °6 

 respectively for substance made from furfurol and from mucic acid. 

 The chief constituent of the oil under investigation was thus shown to 

 be furfurol. From the higher boiling portions, I have as yet been 

 able to isolate no well-marked substances. On distillation, the ther- 

 mometer rose slowly to over 300°, and even after long fractioning 

 there appeared to be no tendency towards constant boiling points. 

 By far the greater portion was insoluble in alkalies, and I could obtain 

 no characteristic derivatives by the action of various reagents. 



# Ann. Chim. Phys., [2] Ixiv. 279. 

 t Ann. Chem. u. Pharm., cxvi. 267. 



