NOTE ON A SPECIMEN O F ANCIENT RUSSIAN OAK 171 ABSTRACTS OF PAPERS PUBLISHED IN OTHER JOURNALS. FOOD AND DRUGS ANALYSIS. Composition of Roman Pomade. L. Reutter. (Comptes rend., 1916, 162, 470-471.)-A Roman vase discovered at Ticino contained a yellow ointment, which melted at about 58' C., and was partially soluble in petroleum spirit and ether. The analysis indicated that it consisted of a mixture of beeswax and fat, with the addi- tion of storax and oil of turpentine. The presence of tartrates suggested that it had been macerated with wine, while the colour was apparently due t o henna, C.A. M. Researches on the Detergent Action of Soap. S. A. Shorter. ( J . SOC. Dyers and CoL., 1916, 32, 99-109 ; through J. Xoc. Chem. Id., 1916,35, 549.)-The observa- ons in connection with these researches were carried out with the stalagmometer,172 ABSTRACTS OF CHEMICAL PAPERS an instrument of the type of a pipette, filled with benzene or other immiscible liquid, designed to deliver drops from its upturned point when held below the surface of the solution to be tested.The number of drops formed in the discharge of a measured volume was counted, giving the ‘( drop number,” which is approximately inversely pro- portional to the surface tension ; a large drop number corresponds to a large ‘; surface activity.” I n a solution of soap consisting of free alkali and acid soap resulting from hydrolysis, the latter exercises no ‘‘ surface activity ” ; this was proved by means of the stalagmometer filled with pure benzene when immersed in soap solutions to which increasing quantities of hydrochloric acid were added.As the decomposition of the soap progressed, the drop number fell until it became practically equal to that obtained with pure water. The influence of alkali in soap solutions was studied by adding oleic acid to the benzene and comparing the increased drop number with that of pure benzene; soap solutions containing various ratios of alkali to fatty acid were employed.I n a “ neutral” soap solution, with molecular ratio of acid : alkali = 1.0, the ;‘ surface activity ” of the free alkali due to hydrolysis was only about one-fifth of that of the undecomposed potassium oleate ; it was slightly more in a more alkaline soap, and con- siderably less in one with higher acid : alkali ratio.The (( surface activity ratio ” increased only slightly with increase in concentration of the soap solution, because the degree of hydrolysis decreases in more concentrated solutions. Hence the deter- gent action of solutions of neutral or slightly alkaline soaps is due mainly to the undecomposed soap. The view that the detergent action of soap is due to its colloidal nature is supported by observations carried out on (‘ Sapon,” an alkaline detergent containing no fat, prepared by the action of strong alkalis on cereals.This colloid detergent showed a I ( surface activity ” in the stalagmometer comparable with that of soap solutions ; this method, therefore, is capable of determining the value of a deter- gent containing (‘ surface active ” colloids other than salts of fatty acids. The addi- tion of alkali to a soap solution increases the t L surface activity” of the soap, even to pure benzene, and its detergent action is improved, probably by slr modification in a favourable sense of its colloidal condition ; the addition of saline electrolytes also increases the I t is suggested that this action of alkali on the soap may be quite as important as its specific action on the fatty acids of the grease. surface activity,” but in a minor degree,