100 YEARS AGO

One of the latest departures of the experimental psychologist consists in prodding people with a pointed instrument when they are asleep to find out how much excitation is required before they begin to move, and how much it takes to wake them up. This method is embodied in a paper on “Experimental Investigations on the Depth of Sleep” by Drs. Sante de Sanctis and U. Neyroz, of Rome, a translation of which is given in the Psychological Review for May. The instrument employed is called a Griessbach ethesiometer (made by Brändli, of Basle), and may be used with either a sharp or blunt point. It measures the stimulus necessary to induce subconscious reaction, and that applied at the waking point... The [resulting] curves are all of zigzag form, and the experiments may perhaps suggest a practical application in the case of subjects who find it hard to wake in the morning, and who may overcome the difficulty by timing their sleep so that the waking point is at a minimum when they wish to rise.

From Nature 5 June 1902.

50 YEARS AGO

Progress in the field of sound recording was amply demonstrated in the annual exhibition of the British Sound Recording Association, held at the Waldorf Hotel, London, during May 17–18.... At long last the traditional wax cylinder for office dictating is being replaced by a plastic belt, which can be folded and sent through the post, as can also a paper disk carrying magnetic material, normally used when clamped on a turntable. In the field of commercial disk records, samples of the narrow-groove slow-speed records, which can play for a long time, have been in hand for some years, apart from talking-books for the blind; before the end of the year, two of the leading companies in this field will be making and distributing such disks. The 'battle of the revs', already in full swing in the United States, will soon be in full force in Britain also. Fortunately, many firms can supply reproducers with all three speeds, 78, 45 and 33 1/3 r.p.m., and all that the user has to take care of is the use of a needle with the correct radius of needle-tip.

From Nature 7 June 1952.