igo 7] Herty — The Pine and its Products. 37 
facts J. H. Long- in 1893 secured specimens from identified 
individual trees, distilled the volatile oils from each and con- 
cluded that while American turpentine rotates the plane of 
| polarized light to the right the variations in the amount of 
rotation in different specimens is due to admixture of the laevo- 
rotatory oil from Cuban pine with the dextro-rotatory oil from 
theLong leaf pine, and as the latter tree generally predominates 
the resultant oils are more or less dextro-rotatory. New light 
has been thrown upon this subject by an investigation carried 
on during the past year in the chemical laboratory of the 
University of North Carolina in collaboration with the U. S. 
Forest Service, by which the results of this study are to be 
published shortly. Through the courtesy of the Service I am 
, enabled to refer to some of the results of special interest in 
this connection. During the past season, at regular intervals 
of four weeks, the crude turpentine has been collected sepa- 
rately from seven Longleaf and seven Cuban pines. A study 
of the oils distilled from these specimens has shown a marked 
variation in the rotation of polarized light. The variation 
exhibits itself not only in the oils from the two species of 
pines, but even among those from the same species. The 
Longleaf pines generally yielded dextro-rotatory oils. One, 
however, yielded a laevo-rotatory oil, while another scarcely af- 
fected the plane of polarization. The Cuban pines gave gen- 
erally laevo-rotatory oils but through wide variations, one of 
them effecting only a very slight rotation. In the case of 
each tree, however, the rotation of its oil was found to be 
practically constant throughout the season. 
The rapid rise in the price of spirits of turpentine during 
the past few years has led to frequent adulteration and the 
offering for sale of many substitutes. The producer, tempted 
by the great difference in price of spirits of turpentine and 
kerosene, has frequently mixed the two. The remedy was 
peculiar. Seeking to advance the price by producing less 
spirits of turpentine, the operators soon found that their suc- 
cessful effort to curtail had been fully off-set by the addition, 
