A Simple Extendable Pointer The chemist's proclivity to conduct seminars using projection slides is well known. I t is also common knowledge that the typical seminar speaker is forced to resort to the use of s. yardstick, a window pole, or some other equally cumbersome device for a pointer. A collapsible, durable, inexpensive pointer can be conveniently constructed from a discarded automobile antenna. Center the antenna base within a 3 1 / 1 in. rubber bicycle handle bar grip, and surround i t with a thick suspension of plaster of Paris to the rim of the grip. Support the antenna in the vertical position for a few hours while the plaster hardens. A pointer made in this way can be extended easily from 23 to 59 in. I have wed one for more than two years, and it still works well.
Volume 43, Number 5, May 1966
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