Science Siftings

New Zealand Tablet, 28 July 1910, Page 1199

Science Siftings

BY ‘VOLT’

A Counting Machine.

There has been installed in the Auckland branch of the Bank of New Zealand three counting machines. These machines, which are similar in appearance to typewriters, not only list amounts, but also record the total simply by the clerk in charge pressing a key at the end of the listing or at any other time. They can add, subtract, multiply, or divide. They can count if required the number of documents going through them, and can also list two separate columns. The operating is very simple. As long as the operator presses the right key the result must be accurate. Even if the wrong key has been pressed, the mistake can be rectified without leaving a trace on the manuscript, as the record is not made till a handle is moved. The machines are fitted in such a way that they can also, if necessary, be worked by electricity. The machines are stated to be great labor-saving devices, and if the Auckland experiment is satisfactory they will be installed in all the principal offices of the bank. The Color of Flowers. It has been found that the color of flowers can be altered by scientific cultivation. For instance, there is a species of wild primrose, whose lemon-colored flowers vary only in slight degree. Cultivation has produced from this very plant a pure blue variety of primrose, which has retained a general color, but developed all shades from the palest sky blue to the deep blue of the corn flower. The Chinese primrose when first cultivated in the garden bore only red and white flowers. Other colors are now produced, not only violet, but also blue, although not so pure a blue as in the case of the cultivated wild primrose. Another example is offered by the gladiolus, which formerly bore only red and white flowers, but has recently been developed into a blue-flowering variety. A case of somewhat different character is presented by the asters, which have long shown a great variety of colors, but in which recently a great many new shades have been produced. It has been found that in making these experiments those proving successes were invariably with flowers that showed some disposition, even if slight, to vary in shading. The Exercise of Vision. Through the experiments of expert oculists it has become known that in reading an easily comprehensible text there is a regular change between pauses of rest for the eye and its movements. The number of these pauses, however, is much smaller than the number of letters over which the eye glides, and it remains in the case of the same person almost unchanged as long as a fluent text is used. If the text becomes more difficult in the meantime, the number of pauses is increased a little, and where attention is given exclusively to the formation of words, as in reading for correction, the number becomes three times as large. It seems certain that reading is effected exclusively during the pauses of rest. On the average, the eye glides, during a definite movement on the line, over a space of 1.52 to 2.08 centimetres, or nearly an inch, a space containing from twelve to thirteen letters. The rapid change of the black and light textual elementsthe letters and the spaces betweenmakes it impossible for the eye to recognise the letters while it is in motion. By a very brief exercise of vision while the eye is still, four letters without exception, five at the most, can be recognised at the same time, even when they do not occur in a sequence of words. In the case of such a sequence, however, four or five times as many letters can be read during the same interval of vision. In the short pauses off rest while reading one recognises the words solely from their word formation as the eye sees it—that is, if the letters are not too large, and such recognition is by so much easier as the words show themselves more characteristic and fluent to the reader. Even a beginner can therefore with a little practice enable himself to read not only without spelling, but with a visual grasp of whole words at a time.