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. 

 Oil : 1, 000 



Rosin___ 400 



25 per cent sodium hydroxid solution 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-SOLVEJSfT 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 -g-^-, 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 



