Authentic Science Fiction Monthly No. 72 — page 67: what you’re looking at

Machine-transcribed from the original scan — historical spelling and the odd misread are preserved.

AUTHENTIC SCIENCE FICTION mans, dependent on human minds and the accuracy of human instruments. Accurate clocks, similar to the chrono- meters of ocean-going ships, will be carried to the planets and beyond. For the spring-controlled type of clock is the simplest and most effective method of measuring time. It can be built to operate just as accur- ately under an acceleration of ten gravities as it will in free- fail or the test room of a factory. Under any conditions in which a human can exist, clocks will continue to run smoothly. Already, sealed wrist watches are used by airline pilots and underwater swimmers at widely varying pressures. And they use only one 100,0C0th of a horsepower. Temperature compensation is automatic, whilst non- magnetic alloys nullify the effect of enormous magnetic fields. Synthetic jewels keep the bearings turning smoothly, absorbing the 864,000 move- ments a day and able to show little wear after centuries of use. The most accurate clocks on 66 Earth are the quartz clocks, accurate to one thousandth of a second per day. They derive their meticulous rhythm from the vibration of specially cut quartz crystals. Just as a bell has a certain note when struck, so these crystals vibrate at peculiar frequencies when excited electrically. Electronic circuits then amplify and record this vibration and, to obtain utmost accuracy, three separate quartz clocks are run as a unit and intercom- pared electronically. These clocks take up as much room as an oversized suitcase, most of this being the valve ampli- fier circuits to amplify and measure the vibrations. Ex- cept for their size and deli- cacy, which may be overcome, quartz clocks would be ideal for spaceships. Another draw- back, which. would lessen as technology progressed, would be the presence of another piece of equipment drawing electricity from a _ possibly limited source. The spring clock just needs winding. Ordinary electric clocks will be virtually useless in space; they rely on the number of cycles in an alternating current conicbooks,. con