CONTROL OF SAPONIFIED SOLUTIONS 21 
weighed and the weight of undistilled residue is multiplied by -4 to 
obtain the percentage of high-boiling phenols in the sample. 
Samples of commercial cresol should probably be subjected to 
direct distillation of 25 grams in a 50-cubic centimeter flask, though 
obviously it is possible to recover the phenols from the alkaline 
extract from the estimation of total phenols, as in the case of saj&ni- 
fied cresol solutions. 
TENTATIVE STANDARDS AND RESULTS OF THE EXAMINATION 
OF SOME COMMERCIAL SAMPLES 
For purposes of control it is necessary to set entirely detinite 
standards for performance and composition. §jich standards must 
be rigorous enough to insure adequate quality but at the same rime 
liberal enough to assure a sufficient supply of the commercial product 
at a reasonable price. In this section the writer accordingly oilers 
in a wholly tentative way provisional standards formulated on the 
basis of his own experience, together with the results of the examina- 
tion of a number of commercial samples. The latter have been se- 
lected to cover the widest range of composition thus far met and 
include some samples of material supplied as " Liquor Cresolis Com- 
positus. U. S. P." 
In the chill test the tubes were packed in sufficient cracked ice to 
insure a temperature of 0° C. throughout the period of exposure, 
which was set at three hours. A shorter period is not always suffi- 
cient to allow a tendency toward separation or gelatinization to be- 
come plainly, manifest. The rate and degree of solubility were 
determined in water at 25° C. and two minutes was tentatively 
adopted as the maximum period which should be necessary for 
complete solution. 
The Bureau of Animal Industry (G) at present requires a soap 
content equivalent to not less than 28 per cent linseed oil or soybean 
oil. The saponification values of these oils range from 187 to 200, 
so that if completely saponified 28 per cent of glyceride will be 
equivalent to between 3.73 and 3.99 per cent of combined sodium 
hydroxide. It is important that saponification should be practically 
complete ; therefore it appears fitting to require that the alkali com- 
bined as soap shall be equivalent to not less than 3.6 per cent sodium 
hydroxide. Perhaps the excess alkali may be justifiably limited to 
not more than 0.5 per cent, expressed as sodium hydroxide. A mini- 
mum content of 50 per cent total phenols is already required by 
B. A. I. Order 273. Perhaps the maximum limit might be placed at 
53 per cent. 
The temperature at which to stop distillation in the determination 
of high-boiling phenols was tentatively fixed at 207° C, corrected, 
midway between the boiling points of meta- and paracresols (202° 
C.) and the lowest-boiling xylenol (211.5° C). In addition, a few re- 
sults are given at 210° C. and 215° C. corrected. The thermometer 
was standardized by distilling a sample of paracresol of assured high 
purity in the apparatus used for the determination of high-boiling 
phenols and reading the temperature at the middle of the distillation. 
All temperatures were reduced to 760 millimeters barometric pres- 
sure at 0° C. by first reducing the observed barometric reading to 
0° C. (8°=1 millimeter) and then correcting for the difference 
between the latter and 760 millimeters (1 millimeter= 037° C). 
