428 CURRENT TOPICS. [J. 17. 1.

U. labrusca L, a typical representative of which is the Concord grape. Another form much esteemed is U. riparia Michx, which is the origi- nal of the Clinton grape. In the South, V. rotundifolia Michx, best represented by the Scuppernong or Muscadine, and U. cestivalis Michx, represented by the Norton grape, are principally in use.

Authentic samples of grapes from many sources were tested, and it was found that when the plant was derived from V. Iabrusca or hybrids in which this predominated, methyl anthranilate was present, but the fruit of V. vinifera does not give evidence of it. It appears that this species does not thrive in the United States, east of the Rockies, but is very successfully cultivated in California. The great grape-growing industry of that region is said to depend upon the cultivation of the European species. The literature of grape-culture shows that about 6000 varieties have been described. Even in California, however, many of the vines are growing as grafts on American roots, and it is thought probably that in time all the vines will be thus grafted. A number of samples of commer- cial grape-juice were tested, most of which contained the ester.

H . L .

Oxidized Kerosenes as Fuel.--This problem has been under- taken at the laboratories of Carnegie Institute of Technology, Pittsburgh, in experiments to determine the relative efficiency of kerosenes and oxidized kerosenes as fuels. According to a report by Dr. J. H. James, Head of the Department conducting the experi- ments, oxidized kerosenes cause less " knocking " tendencies than the straight when used in a kerosene engine, but have approximately the same power development notwithstanding that the thermal value is one-eighth less. Doctor James attributes this efficiency to the better "clean up " in the combustion of them.

The experimental work at Carnegie gives promise that oxidized kerosene, which is manufactured by catalytic oxidation from low- grade petroleum, may become a useful fuel. H . L .

Studies of Vitamins.mAt a recent meeting of the Royal Institu- tion of Great Britain, Dr. Arthur Harden presented a summary of present knowledge on the question of vitamins. Experiments on these substances are difficult and tedious. It seems to be established that vitamins A and C are fairly resistant to moderate increase of temperature provided air is excluded, but deteriorate rapidly when exposed to oxidation. Vitamin B is less affected by heat and aera- tion. All three vitamins originate in the vegetable kingdom, and in view of this fact, it is interesting to recall the Biblical endorsement of the " green herb for meat " as given to the residents of Gan-Eden. In fats, the vitamin seems to reside entirely in the unsaponifiable portion, and as this usually consists largely of cholesterol, which has no value, it is evident that the amount of the really active substance is very minute. Vitamin A does not appear until the photosynthetic actions occur. Vitamin C is not in seeds, but appears when they