From the July 11, 1931, issue


Grasshopper outbreaks in Nebraska and South Dakota may be only the advance guards of a much worse and more widespread insect horde to arrive before very long if hot waves continue to sweep the country. So say entomologists of the U.S. Department of Agriculture. The coming of these insects in June was in a sense premature, they state, for even in bad grasshopper years the pest does not ordinarily assume serious proportions until July.

Just how bad the grasshoppers can be expected to be in the West this year it is impossible as yet to estimate. The Bureau of Entomology, however, has a number of scouts in the field, investigating the areas most under suspicion as probable breeding centers of the hoppers, and battle plans are being laid. The principal means of combat against the grasshopper armies is chemical warfare: poisoned bait, consisting of a molasses-sweetened bran mash loaded with sodium arsenite or other arsenical, is distributed where they can find it.


A super-giant variable star with light flashing up and down so vigorously that its brightness changes from 12,000 to 33,000 times that of the sun within less than 1 month has been found in the Large Cloud of Magellan, a distant mass of stars visible in the sky of the southern hemisphere. This star is but one of many super-giant variables in the great star cloud that lies at a distance of 90,000 light-years from Earth. A light-year is approximately 6 trillion miles.


An instrument that will measure the force of an earthquake that shakes it was described by Prof. J.A. Anderson of the Mt. Wilson Observatory, before a seismologists meeting in Columbia, S.C., recently. It consists essentially of a pendulum free to swing in a given plane but normally resting against a stop. It can be adjusted to indicate a given force of movement by the angle of its swing.

When an earthquake strikes it, the pendulum swings away from its stop. This opens an electric circuit and causes a semaphore on top of the instrument to drop. It is planned to use seven such pendulums on each installation, each set to indicate a different earthquake force. Then the operator, looking at the set-up after a quake, can tell by the number of semaphores that have dropped how severe the earthquake was. Then simply by resetting the semaphores, he leaves the instrument ready to register the force of the next earthquake.

From the Nature Index

Paid Content