VoI.XVII No* 20 Approximately 80 alumni, and students of Highacres, gathered in our main lounge and cafeteria on Tuesday evening to listen to the 100th anniversary program that was transmitted by telephone from the newly dedicated HetzsO. Uni an Building on the main campus. After listening to speeches by Gov. George Leader, Speaker Hiram Andrews, and President Milton Eisenhower, those attending joined with our College Community Chorus in singing the favorite songs of Penn State and the Alma Mater. The Center provided refreshments to conclude the evening. Fisw students here at Highacres ever see the inside of Mr* Sard's Physics Lab and so miss all the interesting (and complicated) contrivances that are used there. One of these was recently assembled by Mr, Ward - a device known as a tuning fork calibrator The Fhysics classes use tuning forks in scone of their experiments and naturally must know the exact number of vibrations-per-second of each fork. Tbie number'is stamped on the fork, but (according Ward) since the students carOf take anyone : s word for anything, they have to find cut whether or not the given number of vibrations is accurate with the number stamped on the fork. The set—up for obtaining the information includes a revolving disk punctured by concentric rows of holes * In the experiment, a beam of light is directed on one row of holes as the disk turns. The light then makes regular pulses as it shines through one hole after another, and when this succession of light rays falls on a photoelectric cell it produces a an pulsating current of electricity. When amplified, this pulsating current tone. The frequency of the vibrations of this tone can be increased or decreased by changing the speed at which ohe disk rotates* If the tuning fork is struck ana held in front of a microphone, it will produce a tone simultaneously with the other,. If the fork is vibrating at not quite the same rata as the tone produced by the photoelectric cell, a definite, regular 'beat' will be audible. This 'beat’ proves that the tuning fork is not vibrating at the perscribed