REMARKABLE INSTRUMENT PHOTOGRAPHS ATOMS BY MILLIONS

Manawatu Times, Volume LIV, Issue 6801, 3 January 1929, Page 12

REMARKABLE INSTRUMENT PHOTOGRAPHS ATOMS BY MILLIONS

NEW DEVICE RECORDS MANOEUVRES OF MINUTE PARTICLES. PASADENA, Calif. Now that Dr. Robert Millikan, executive head of the California Institute of Technology, has succeeded in dissecting an atom, his accessories have gone a step further by perfecting an instrument which will photograph these minute particles at the rate of 100.000,00 per second. This gigantic camera is known as a cold cathode ray occillograpli, and is 10 times faster than speed cameras used by newspapermen. It is more intimately known as “Ossie,” according to Prof. Royal W. Sorensen, head of the electrical engineering department of the Pasadena institution.

Pictures taken by this machine which docs not resemble a camera, although it uses standard photographic equipment, mean little or nothing to the layman, but apparently tell an interesting story to the electrical engineer. Claude D. Hayward, instructor in electrical engineering, is now making preparations to perform the first- experiments with the now piece of equipment and will set forth the results in his doctor’s thesis-.

“Ossie” weighs approximately \ 750 pounds, and was built by the Western Electric Company, at a cost of £2,500. Until now it has been impossible to photograph electrical phenomena as the fastest oecillograph previously perfected worked with a maximum speed of one-ten. thousandth of a second. It is possible and entirely probable that new and revolutionary applications of electricity will bo developed as a result of experiments to be conducted. The mechanism consists of two units. On the top of the major unit is a large ablong -wooden housing, from one end of which puotrudes an iron funnel or vacuum bell. Within the wooden box is the cathode tube which serves to separate the electrons from their positive nuclei and allows them to shoot from a small hole into the vacuum bell. The film is located inside the bell.

In order that the cej'.rons may record significant tracings on the film, they are deflected slightly from their straight path by being passed through

an electrostatic or electromagnetic field. The cathode tube may be considered as a machine gun for an illustration, the electrons as as bullets and the film as a target.

There is a small round window in the vacuum bell through which an observer may witness the electric bombardment. On the second unit are mounted a pump for exhausting the air in. the bell, a motor, and the timing and switching apparatus. The pump is made necessary because the vacuum bell must be opened each time a new film is inserted and it is therefore necessary to correct the air pressure after each exposure.