A I
White P P ~sol. . in HNOI
B White ppt. sol. in acids
White t . sol. in NHdOH
D E P C RedWhite White No ppt. brown ppt. sol. ppt. sol. slight ppt. sol. ioaeids in acids cfferves. in acids with ence evol. of
Slight ppt. sol. in NHaOH Glass etched b y fumes
2 gases White evolved ppt. on htg. inrol. limewater in acids milkg except eombus- mnc. tible HeO.
C
H
I
N o ppt.
co,
J
White ppt. insol. in acids except m e .
H,SOa
No ppt. orange
solution
N o ppt.
No reaction
White Evol. o l ppf. COI Colloidal Odor SO,
A D D ~ O N ADATA L All mlolutioas are colorless except solutioas B and D which are light yellow. Solutions G, H , and 1 are acids. Solution A givesthe brown ring test. Solution E gives a m e n Same test and rolution I n yellow flame test.
(Answers to be published in the next issue.)
Iron Salt Recommended a s Curefor Poison Ivy. Poison ivy meets its match in the iron compound known as ferric chloride, according to a new booklet on the toxic weed bv Dr. James B. McNair, which is being issued by the Field Museum of Natural History. Dr. McNair discovered in the course of exhaustive researches on the chemical nature of ivy poison that this substance is rendered insoluble and thus made harmless by chemical union with iron. A number of soluble iron salts, he says, are effective against poison ivy, but he has found ferric chloride t o be mast suitable. His treatment calls for a mixture of one part by weight of ferric chloride with ten of alcohol and ten of water, t o be washed on the skin and allowed t o dry there before one goes into places where poison ivy grows, and also after such possible exposure. This, it is claimed, will entirely prevent the development of ivy poisoning in the great majority of cases.-Scienu Setvice Franklin Institute to Honor X-Ray Tube Inventor. Invention of the type of X-ray tube now in almost universal use in hospitals and laboratories has won for Dr. W. D. Coolidge, assistant director of the General Electric Company's research laboratory, the Howard N. Potts Medal of the Franklin Institute. This medal, of gold, will be awarded t o Dr. Coolidge, says the citation, "in consideration of the originality and ingenuity shown in the development of a vacuum tube that has simplified and revolutionized the production of X-rays."-Sciencc Service American Competition in Glass Stimulates German Research. A new scientific institute has been founded in Berlin for the study of the -physical and chemical problems underlying silica compounds and all the industries that use them, including glass factories, brick and tile yards, pottery works, lens laboratories, and many others. The advance of the silica industries in the United States based an American science during the past two decades is recognized as the stimulus of the new movement. In making its recommendation the committee said, "We in Germany have had t o acknowledge to our cost that the Americans have known better than we how to carry out in practice the spirit of scientific advance."-Science Service ~
