Physicists Twirl Atoms, Aim Radio

Sixty miles up in the sky there is a cloud of electricity. Tonight, slowly and mysteriously, it will vanish. Professor Roland B. Holt wants to know why.

Holt heads one of the dozen or so research projects that the Department of Physics and the Department of Engineering Sciences are now working on. With the help of graduate assistants, he is trying to solve this cosmic whodunit and thus win another battle in Harvard's war against the unknown.

Up In the Air

Holt studies the region high above the earth, where the sky is always black and the temperature may be 1000 degrees. By working in a Jefferson Hall laboratory, he is learning the processes which might explain the nightly disappearance of the electron cloud.

His work in the ionosphere ties in with the research of Professor Harry R. Mimno. Mimno is sending short-wave radio beams into the sky, to study how they bounce off the upper layers of the air. What he finds may change the future of radio transmission.

Mimno will soon finish building a parabolic steel reflector in Lexington. Bigger than the average House living-room, the reflector will aim radio waves as an automobile headlight aims light rays.

Both of these men are working under Navy contracts, like most of the research physicists in the University. The contracts have been a gold-mine to the science labs, for the departments themselves have enough cash for only two or three projects.

Navy Contract Number One has gone to Professor Emory L. Chafee for research in electronics. One of Chafee's jobs is to invent new kinds of vacuum tubes--he is now working on one that spins a light wave around a beam of electrons. The two interact to strengthen an electric current.

Chafee is also listening to the noise an electric wire makes when it is heated. The hot molecules vibrate faster and make strange sounds over radios.

Some of his assistants are working with microwaves, trying to pick out one special wiggle from thousands of other wiggles. In one experiment, they hitched a microwave to a color of light, and singled it out that way.

Others are studying aerials, and how their shape and size affect the waves they send. Antennas with a cone-shaped top, for instance, behave much differently from those with a ball-shaped top.

The Department of Engineering Sciences has three more projects. Professor Frederick V. Hunt is studying sound in his anechoic chamber, whose walls sponge up over 99 percent of every noise. Professor Howard H. Aiken is building his fourth super-brain calculating machine, faster and smarter than before. Professor Howard W. Emmons is working in mechanics.

Down in the basement of Lyman Labs, Nobel Prizewinner Percy W. Bridgman is learning what happens to things when you squeeze them hard. With huge hydraulic presses, Bridgman has squeezed one cubic inch of matter with the pressure of 1000 trailer trucks.

In other labs, Professor Kenneth T. Bainbridge is studying the mass spectrograph, and Professor Edward M. Purcell is working on nuclear-magnetic moments, which isn't half as simple as it sounds.

But the big noise around the Physics Department is always the atom-smasher. Research Fellow Lee L. Davenport has already assembled most of his cyclotron, and is now tinkering around with the small parts.

Last year, amid reams of newspaper ballyhoo, Davenport received the magnet for the machine--a magnet so strong that it could yank hammers out of people's hands and stop all the watches hear it.

In January, he drained 99.999999 percent of the air out of the cyclotron in a vacuum test. The main chamber has to be free of air molecules when in operation, so that the spinning electrons won't bump into anything.

Davenport plans to finish the whole thing this term. Then the press will hold another field day, and the public will finally get into the grey, windowless building on Oxford Street. What they'll see will be the biggest machine in the University push the smallest thing in the Universe at the fastest speed made by man.

The Crimson this week starts a policy of complete coverage of the projects and discoveries of the University's science departments. This article attempts to fill in the background on the Physics and Engineering Departments, and get up to date on their present undertakings. It is the first in a series of three stories.