| Wt. of pipette before | 18.7660 |
| Wt. of pipette after | 14.7160 |
| Wt. of resin used | 4.0500 |
| Temperature before | 3.52 |
| Temperature after | 3.71 |
| Change in temperature | .18 |
| Volume | 37 cc. |
| Constant for solvent | 3280 |
| Approximate molecular weight | 2000 |
Combustions were made and the following data obtained.
| Wt. of boat | 3.4722 | 3.4720 |
| Wt. of boat and resin | 3.6355 | 3.6220 |
| Wt. of resin | .1633 | .1500 |
| Sulphuric acid tube | 79.1051 | 79.3865 |
| Tube plus water | 79.2073 | 79.4770 |
| Water | .1022 | .0905 |
| Hydrogen equivalent | .01136 | .01006 |
| KOH bulb | 49.4316 | 50.8720 |
| Bulb plus carbon dioxide | 49.8350 | 51.2430 |
| Carbon dioxide | .4034 | .3710 |
| Carbon equivalent | .12102 | .1010 |
| Percent Carbon | 67.31% | 67.3 |
| Percent Hydrogen | 6.9 % | 6.7 |
| Percent Oxygen | 26.8 % | 27.0 |
The total resins when placed on the end of the tongue produced a marked stinging sensation followed by a local anaesthesia. After the first stinging was produced the sensation was rather pleasant. The local anaesthesia persisted a long time, giving a sensation much the same as that produced by cocaine. The barium and iron acids also produced this local anaesthesia, but the initial stinging sensation was much more pronounced, which was probably due to the acid nature of the substance.
THE BARIUM ACID.
The resinous material used and spoken of as the “Barium Acid” is the material prepared and so named as given under the “Method of Separation”.
PHYSICAL PROPERTIES:—Dark reddish brown in color, syrupy in consistency and has a characteristic odor; heavier than water; soluble in benzol, ether, alcohol and acetone, but insoluble in petroleum ether and water.
This resin constitutes about sixty percent of the total ester resins; i.e. the resins left after the free acids have been removed with aqueous potassium hydroxide.
An analysis of the barium salt obtained by precipitation from the potassium soap was made and the following data obtained:—
| Wt. of substance used | 1.1715 | .5860 |
| Wt. of barium sulphate | .4430 | .2205 |
| Barium equivalent | .2606 | .1298 |
| Percent barium | 22.2% | 22.1% |