From the December 12, 1931, issue


Everybody has heard of Barro Colorado, the hill that was turned into an island, and was set aside as a great animal sanctuary; but only a few persons have ever set foot on it. In the nature of things, an animal sanctuary cannot be opened to crowds of visitors, so the only callers are the few scientists who have to meet the birds and beasts and plants on business.

But strangely few have heard of two other more recent developments in the Canal Zone, which open to anybody who cares to come many of the privileges reserved to scientists alone on Barro Colorado.

These are the newly opened forest reserve, a dozen miles northwest of the city of Panama, and the Canal Zone Experiment Gardens, nearby.

Many of the creatures that are in the forest you will never see by daylight. Either they see you first, or hear, or smell you, and quietly keep out of your way, or they do not roam abroad by day at all.

To get records of these nocturnal prowlers, the Barro Colorado scientists have resorted to trapping by camera–setting up a camera with a big charge of flash powder and a string-and-trigger arrangement for firing it when an animal touches the string. This has obtained superb photographs of such rarities as the tapir, that strange animal that looks like the Elephants Child before the Crocodile pulled his nose; the puma and the ocelot, the two big cats of the region; and the trouser-legs and shoes of a night-wandering man, a trespasser who hadnt any business on the island. If that chap didnt know what a camera-trap set-up is, he must have thought a whole battery of artillery had opened on him when that big flash went off. He never came back to report his actions.


Using the new super-microscope invented by Dr. Royal Raymond Rife of San Diego, Dr. Arthur Isaac Kendall of Northwestern University Medical School has seen for the first time the exceedingly minute moving bodies that apparently carry the life of bacteria when these are induced to dissolve into a form that will pass through the pores of the finest porcelain filter and still remain alive and able to resume their microscopically visible bodies upon suitable treatment.

The work was done at the Pasadena Hospital, and will be reported in the official publication of the California Medical Association, California and Western Medicine.

The material used by Dr. Kendall was a culture of the typhoid bacillus, ordinarily a fairly large germ, easily visible under the high-powered lenses of a compound microscope. By feeding it on his recently evolved K medium, which apparently has the power of causing all visible bacteria to pass over into an invisible, filterable phase, Dr. Kendall induced the bacilli in his cultures to go through this change. Under the highest power of the ordinary microscope, he could see nothing moving in the fluid, except a swarm of rather active little granules that were visible only as tiny motile points.


The incessantly penetrating cosmic rays that bombard Earth from the depths of outer space smash the hearts of atoms and let loose speedy particles, Dr. Robert Andrews Millikan, Nobel prize physicist of the California Institute of Technology, announced in New York upon his return from a two and a half months good-will trip to Germany and other parts of Europe.

Disintegration of the atomic nucleus by the cosmic rays was discovered by Dr. Carl D. Anderson, an associate of Dr. Millikan at the Normal Bridge Laboratory of Physics at Pasadena, during research planned jointly by Drs. Millikan and Anderson. The results were communicated to Dr. Millikan while abroad so that he might discuss their import with physicists who have been studying atomic disintegration at the Cavendish Laboratory at Cambridge for the past decade.

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