SCIENCE SIFTINGS

New Zealand Tablet, 3 November 1921, Page 46

SCIENCE SIFTINGS

:-tJ| . By "VOLT” ■ . ===

WIRES AS WEATHER PROPHETS. To trained ears, telegraph wires act as excellent weather prophets. / Predictions as to the state of the weather can be made ■ from twenty-four to thirty-six hours in advance by an appreciation of the pitch, strength, and quality of the tones produced by the wires. Rain, snow, and storms can be foretold with considerable certainty. ( High shrill notes precede heavy but brief falls of rain or snow, while deep humming tones indicate rainfalls which are both brief and light. Buzzing tones indicate a change in the weather; indefinite soft, humming tones of medium strength indicate a longer continuance of damp weather. ' It is difficult to describe the tones in mere words. They must be heard repeatedly in order that the mind may form consciously or subconsciously an idea of the weather condition to which they correspond. OLD MUSICAL INSTRUMENTS. The''earliest keyboard instrument known is said to be the hydraulic or water-organ of the second century 8.C., a Greek invention. This was followed by the monochord, an instrument consisting of a long box of thin wood with a bridge fixed at each end and an intermediate bridge, over which was stretched a single wire or catgut string hence the term monochord. This is supposedly invented by Pythagoras, in the sixth century 8.C., but its principle was used by the Egyptians twenty-four hundred years before. The monochord which was used for many centuries in Greek and Roman churches, in training the singers “ the production of tone, was rapidly improved upon, and when the clavis or keys came into use on church organs, about 1000 A.D., they were likewise applied to the monochord. Each key had a small brass wedge, about an inch high, which as soon as the key was pressed down by the finger would prick the string at the proper division and thus produce the correct tone. The use of the clavis thus led to an increase in strings. Of. the musical instruments of early times, the Psaltery is perhaps the one more often reproduced in sculpture and painting than any other stringed instrument as demonstrated in the art of the fourteenth and fifteenth centuries. This instrument, which was triangular, square, curved or harp-like in form, was often carried by a ribbon Ground the neck or, when in a case, was removed when used and placed upon a table or in some other convenient position. Its strings were operated by means of a plectrum whichwas held in the fingers of the performer and which today is only used in playing the mandolin or instruments of this character. With the demand for greater volumeof sound, the Spinet (the invention of which'is attributed to Giovanni Spinnetti, and from whom the name of “Spinet” was supposedly derived) became a popular instrument until the eighteenth century, and, owing to its use by young women, was popularly termed in England a “Virginal.” This instrument had one string to every note, which was picked by a crow-quill fastened to a jack resting upon the key,, which sets the string in vibration when the key was pressed down.’ Spinets were built in various sizes, the small ones being easily carried about, and In Italy were usually made without legs or a stand, as they were often used in gondolas for the accompaniment of singing. The Spinet was made with the keyboard outside as well as inside the which was decorated most elaborately.

A single sunbeam is enough to drive away many shadows.—St, Francis of Assisi. I