28 



OLEOBESINS OF SOME WESTERN PINES. 



CONCLUSIONS. 



The volatile oil of Pinus contorta consists almost entirely of l-fl- 

 phellandrene. The colophony contains about 80 per cent abietic 

 acid. 



Pinus edulis Engelm. 



EXAMINATION OF THE OLEORESIN. 



The oleoresin of pinon pine (Pinus edulis) contains very large resin 

 acid crystals and has a characteristic odor resembling thuja leaf oil. 

 It has a specific gravity of 1.0238. 



The average composition as shown by the analysis of five consecu- 

 tive dippings is: 



Per cent. 



Volatile oil 20. 



Rosin (grade I to WG) 76. 5 



Trash 0. 9 



Water (by difference) 2. 6 



Total 100. 



EXAMINATION OF THE VOLATILE OIL. 



PHYSICAL PROPERTIES. 



The oil had the characteristic odor of the oleoresin, due to the 

 presence of a sesquiterpene; the specific gravity was 0.8680; the 

 index of refraction, 1.4707; and the specific rotation [a] D = +19.26. 

 On fractional distillation the results shown in table 6 were obtained: 



TABLE 6. Fractional distillation of the volatile oil of Pinus edulis 



IDENTIFICATION OF CONSTITUENTS. 



a-pinene. The results obtained on fractional distillation show that 

 the oil consists largely of or-pinene. For further confirmation the 

 d-rotatory first fraction was treated with nitrosyl chloride; the pinene 

 nitrosochloride obtained melted at 103 after purification. 



