From the June 19, 1937, issue

LIGHTNING IS CAUSED BY BREAK-UP OF RAINDROPS

June is a month for lightning. Some of its beauty is recorded in the photograph on the front cover of this week’s Science News Letter.

Whence lightning? According to a widely accepted theory, supported by many observations and laboratory experiments, the electricity of lightning is found in the breaking up of raindrops. This condition is realized in a thunderstorm where the updraft is sometimes very violent. This turbulent stream of air ascending breaks up the falling drops, disrupting them and forming positive charges of electricity on them. Negative electricity is formed in the air where the disruption takes place.

There are four kinds of lightning due to differences in the electrical condition of the atmosphere. (1) The usual streak lightning speeding from cloud to cloud or cloud to Earth. (2) Rocket lightning, where the lightning seems to be moving slowly like a skyrocket. (3) Ball lightning (balls of fire in the sky) is seldom seen. It seems to be an illusion or a variation of rocket lightning. (4) Sheet or heat lightning is really not a fourth kind; it is simply the illumination of a cloud or the atmosphere, by either streak or rocket lightning.

RECORDS OF “GIBBONESE” MADE IN JUNGLES OF SIAM

First phonograph records of the “language” of the gibbon, key animal in the evolution of man, have been made this spring in the mountain forests of northern Siam by an expedition from Harvard University, the Johns Hopkins University, and Bard College.

They are expected to constitute one of the more important aspects of the expedition’s pioneering, firsthand study of the natural behavior and physical character of the Asiatic anthropoids. From the expedition as a whole the group hopes to glean important new clues to man’s early development and the jungle origins of his social systems that will aid in unraveling some of the more puzzling problems of human evolution.

To this end, the seven American scientists comprising the party are applying modern psychology, sociology, and anatomy to their examination of the gibbon’s home life, testing primarily the position of the gibbon on the family tree of the anthropoid apes and even of man.

Similar to man physically, the gibbon is gregarious and monogamous as well, facts that lead scientists to believe that in its natural habitat they may find the traces of the origins of man’s most firmly established institutions, his family and group life.

JAUNDICE RESEARCH MAY GIVE CLUE TO ARTHRITIS CONTROL

Discovery that jaundice temporarily checks the progress of chronic deforming arthritis, suggests that this most crippling and disabling of all forms of chronic rheumatism can no longer be regarded as a relentlessly progressive, uncontrollable disease for which no really satisfactory remedy need be expected, Dr. Philip S. Hench, of the Mayo Clinic, Rochester, Minn., told members of the American Association for the Study and Control of Rheumatic Diseases meeting at Atlantic City.

No new method of treating arthritis is ready for application at present. Dr. Hench made this point very clear. The work is still in the experimental stage, and many complex problems must be solved before the stage of treating patients is reached. Dr. Hench reported investigations on these problems, which he has been carrying on since 1929.