20 The Philippine Journal of Science 1922 
We have not used the aspiration method of Smith,* for it 
is very slow and we have not succeeded in getting good results 
by it. 
5. The free salicylic acid was determined colorimetrically, 
applying a method based on the tests given by several phar- 
macopeias. These state that 0.1 gram of aspirin dissolved in 
5 cubic centimeters of alcohol and 20 cubic centimeters of water 
must give no color with ferric chloride solution. The Phar- 
macopeeia of Japan allows a light coloration in this test, which 
indicates that under local climatic conditions the best samples 
undergo partial dissociation. 
A similar procedure was adopted in our experiment. Using 
solutions of salicylic acid of different concentrations and per- 
forming the test under identical conditions we compared the 
coloration in Nessler tubes. 
In this way the results in the eighth column of Table 2 were 
obtained. 
TABLE 2.—Chemical constants of aspirin. 
Acidic value, Saturation value. | Bromine number, Free acids. 
Sample, 1 gram. | me N ae hs N int haw Corre- 
sodium |sponding jum |sponding 0.2 spondin 
| hydrox- | salicylic | hydrox-| acetic | bromine. ealleylic. Acetic. | Salicylic. 
| ide. acid. ide. acid. acid. 
| 
| 
Pe Oe. oc. “pe Bee 
ee | 27.77} 0.7686! 27.77 | 0.8388 98.815! 0.7666! 0.000 0.000. 
ere e | maz] mei) 27.17] 0.8261, 72.90 | 0.676; 0.018| 0.015 
eee nes | 2.75) 0.7659; 26.96} 0.8235) 67.08 | 0.6171, 0.016 | 0.007 
Wicca 27.92 0.7706) 27.10| 0.9252 65.19 | 0.6007, 0.016 | 0.011 
Wes 27.67 | 0.7609| 27.60| 0.3812 75.00 | 0.6900; 0.018} 0.002 
vn 27.69.| 0.7615 28.26| 0.8391| 66.69 | 0.6185; 0.019 0.008 
VI..w........--| 27.77] 0.7666} 26,26! 0.8161/ 78.84 | 0.7251; 0.011 | 0.006 
Ve 27.40| 0.7562| 28.18| 0.9375| 74.43 | 0.6847| 0.026 | 0.011 
| VITA... 28.77) 0.7940) 27.76| 0.8881 79.28 | 0.7289 0.013| 0.002 
On analyzing the figures set forth in Table 2 it becomes ap- 
parent that certain samples, such as I and VIII, give a figure 
for acidity that is higher than the theoretical figures, and that 
Samples V and VII show the same peculiarity in respect of the 
saturation value. Impressed by these facts we checked the 
figures several times and found no reason to amend them. 
We may say that in the table published by Jones we notice 
the same anomalies in several of his samples. As to the ex- 
"Op. cit. 1037. 
