From the September 4, 1937, issue


The angry grunts of enraged grizzly bears are a common sound at the Yellowstone National Park feeding grounds at mealtime. During July, more than 50,000 people packed themselves into the feeding enclosure to witness a show seen nowhere else on Earth. The enclosure is used to keep the public out; not to restrict the bears. As many as 58 grizzlies and three black bears have appeared at one time for their meals. While fights do start, they rarely last long because food is plentiful and the fighting wastes time.


A radioactive potassium “clock,” latest aid to scientists seeking to know the age of the Earth, indicates that the world is less than 3 billion years old, Dr. Keith Brewer of the U.S. Bureau of Chemistry and Soils reports (Science, Aug. 27).

Radioactive potassium, an isotope of the common variety with an atomic weight of 40 instead of 39, he also indicated, is becoming a “lost element,” similar to radium, whose amount is also gradually diminishing.

Radioactive potassium, K 40, changes over long periods of time into the common variety of calcium, the metal that forms the basis for lime and limestone. Scientists can compute the age of the Earth from their knowledge of how much calcium is to be found today and a knowledge of the rate at which radioactive calcium decomposes.

Results by the potassium “clock” method, Dr. Brewer reported, are in close agreement with estimates of the Earth’s age gained from another radioactive “clock,” that of radium, uranium, and lead.

Radioactive potassium, like uranium, was at one time much more common, he pointed out.


Stuttering may sometimes be caused by oversolicitude of anxious parents who apply the label “stuttering” to the normal repetition of words and sounds in ordinary baby talk. This statement and the implied warning were made by Dr. Wendell Johnson of the University of Iowa’s Speech Clinic in a report to the newly organized American Association of Applied and Professional Psychology at Minneapolis recently.

Nearly 50 little children, most of whom are under 5 years old, have been studied by Dr. Johnson in an attempt to learn how stuttering starts and what causes it. In health and also psychological and sociological factors, the group turned out to be a normal, ordinary bunch of children. A few had troubles of one sort or another. and something like 25 per cent had shifted from left- to right-handedness or done so partially, but for the most part there was nothing out of the ordinary.

For nearly all the youngsters (90 percent) the “stuttering” began with an occasional and effortless repetition of sounds or with prolonged pauses and interjected “Ahs.” Later, these were accompanied by tension, grimaces, and emotion. As a rule, the “stuttering” occurred when the child was thwarted, humiliated, or undecided, or rebuked, Dr. Johnson found.

Such repetitions of sound are not peculiar to the so-called stutterers, but are common among practically all young children, Dr. Johnson emphasized. But in the case of these particular youngsters, the label “stuttering” or “defective” was tagged on to them, perhaps merely because their parents were particularly sensitive to the hesitating speech. The children themselves then began to think of their speech as stuttering, and this in turn led to additional embarrassment and additional stuttering.

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