PINE-OIL AND PINE-DISTILLATE PRODUCT EMULSIONS. 11 
given for the Hygienic Laboratory pine-oil disinfectant (18), with 
certain modifications in some cases. 
The oil, rosin, and alkali solutions were mixed in the following 
proportions and according to the following directions: 
Grams 
GG) ep tayo einen es vy Dh ag ee man rl hae Mw by ee Ei od 1, 000 
TANCOYS( i) SAYS ee ain ee AL MIM =e Wiese eB Wen eM IN A ire Cos DE 400 
POAPSGIcent SOC My OrO X10) SOLUbLO Mss ws ee ee Bia ee ee 200 
The oil and rosin were heated together in a covered porcelain ves- 
sel until all the rosin dissolved. The mixture was cooled to 80° C., 
the sodium hydroxid solution added, and the liquid violently stirred 
for at least 10 minutes. Sufficient water was added to make the 
mixture to the original weight, and the preparation cooled. It will 
be noted, of course, that only the steam or steam-solvent oils are used 
in the Hygienic Laboratory pine-oil disinfectant. Oils Nos. 31717, 
31718, 31719, 31725, and 31726 already contained so much resinous 
material that they did not emulsify well when the full amount of 
rosin called for by the Hygienic Laboratory formula had been added 
to them. Consequently, less rosin was used in these cases, one-half 
the specified amount in the case of Nos. 31717 and 31718, and no 
additional rosin in the others. The usual amount of sodium hydroxid 
solution was added in these mixtures. In mixing with water all 
gave fair emulsions. | 
These products were then used for determining the bactericidal 
efficiency, the results of which are given in the following pages. 
DISINFECTANT ACTION OF EMULSIONS OF PINE-OIL AND OTHER 
PINE-DISTILLATION PRODUCTS. 
STEAM-DISTILLED AND STEAM-AND-SOLVENT PROCESS PINE-OIL EMULSIONS. 
Stevenson (18) claimed for a pine-oil emulsion made from steam 
or steam-and-solvent process pine oil, advocated by him in 1915 as 
a general disinfectant, a phenol coefficient of from 4 to 6, and stated 
that it could be used in any dilution up to z4,, according to the time 
it was allowed to act. The dilution recommended for practical use 
seems to have been based solely on the Hygienic Laboratory phenol 
coefficient. Stevenson also stated that the preparation deteriorates 
with age. Later McCoy, Stimson, and Hasseltine (13), and Walters 
(31) called attention to the fact that this pine-oil disinfectant, al- 
though showing a high disinfectant value against organisms of the 
typhoid group and certain others, is much less efficient than phenol 
or cresol against other common pathogenic organisms, notably 
Micrococcus aureus. 
In order to check these various statements, six samples of pine oil 
were prepared according to the directions given on page 11 of this 
bulletin, and their Hygienic Laboratory phenol coefficients determined 
