SEEING WITH THE EARS.

Pukekohe & Waiuku Times, Volume 5, Issue 163, 7 April 1916, Page 1 (Supplement)

SEEING WITH THE EARS.

MARVELLOUS INVENTIONS FOR AIDING OUR INJURED HEROES. Many brave follows who left this country in the pride of manhood, says an English paper, are bound to return suffering from serious defects, but fortunately clever devices are being perfected to render their lot easier. Hitherto we have looked upon blindness as an appalling infliction, but already discoveries have been made which will do much to improve the condition of those who do not possess natural s : ght. There is every hope for believing that scjence shortly will provide new eves, or rather new means for seeing. Much progress has been made with tins object in view. The retina, marvellous as it is, : s merely a highly-nervous, special kind of skin. There are creatures whose sense of sight consists of their whole body. Hence there is nothing improbable in the view that eventually the human skjn may be trained to receive impressions of light, and so to act as the organ of sight. 1 here is being perfected a marvellous instrument which enables the blind t > detect a light by means of the ear. B, its aid a blind person not only can recognise light, but can locate it and even measure its intensity.

THE EVE OF GREAT THINGS. The instrument is doubtless tsi» beginning of an important series of inventions. So far it merely places a blind person in the position of one who is partially blind, that is, who is able to detect the presence of light. Before long ,it is hoped that the existing instrument will be greatly improved although in any form it will merely be the starting point o the road to a great victory.

To give an exact account of its work Mill be impossible here, but its main principles are as follows: There is a special substance, selenium, which has its electrical resistance alteredi by light; it is due to this substance that it is possible to send photographs from one place to another by means of an electrical wire. In the new instrument tho selenium operates a kind of telephone.

A pairof these telephones are placed on the head, and are attached to a little camera containing the selenium. Assuming this is adjusted for darkness, no sound will be heard when the individual !■> ;n darkness. As soon as any light falls upon the camera a noise is hoard which varies in loudness according to the intensity of the light. Thus moonlight makes a distinct noise, while a considerable roaring sound is heard as the effect of sunlight. In practice it has been found best to arrange the apparatus so that the brightest light produces silence, but the less intense tho light the greater the noise. Thus a blind person fitted with this apapratus ca neasily tell when he passes a shadow. If in a room, ho can tell wnen he is passing a window or doorway. Moreover, the passage of any body between the light will greatly al'fect the instrument.

Many wonderful effects havo o<xn obtained. At present all th e instrument does is to inform tie blind fuscn whether he is in J ; ght or durV.i>v, and the degree of either, iuis, mwevor, is a long stride towards the solution of tnc problem of seeing witr. ju: »\cs.

THE DEAF HEAR. Fortunately it is possible to afford aid more easily in the case of those who are deafened as a result of explosions and so on. It is far easier to cope with deafness than with blindness, particularly as impressions of sounds may be received through other parts of the body than the ear.

Science has already done much to cope with deafness by providing artificial ear drdums and waht not. Yei •: delicate mcirohones can now be obtained which greatly magnify sounds, rendering them within the capacity of persons who normally hear with difficulty. There are instruments in use to convey sounds by way of the mouth instcar. l of through the ears. Hearing is merely the result of vibrations of sound beating upon the drum of the ear, this being communicated to the brain by a series of nerves. Deafness is a defect in this means of communication. Now, a person can hear distinctly by means of his teeth; th's can easily Ik? proved by placing one end of a pocket-knife in the mouth and the other end on a piano. In a similar way, one may communicate sound waves to the brain through any other bony substance, even the skull itself. Starting from these facts an apparatus has been devised which when attached to the head will act ;u an artificial ear. That is, it wilt collect the sound waves, passing the vibrations to the skull, and thus conveying the information to the brain which lies l>eneath. The fact is that we cJo not see with our eyes, hear with our ears, smell with our nose, taste with our tongue, or feel with our skin. It is the brain which acts in every case, and the very useful organs mentioned act as suitable apparatus for the collection and transmission.

In each case certain sorts of vibration are set up, these passing by means of the nerves to the brain. The aim of science now is to find methods of communicating these vibrations.

It is very interesting in this rspcct to notice how persons suffering from sonic physical disability frequently "feel" sensations in parts that have been amputated, the explanation being that the brain lias been acted upon. A somewhat a'lied fact is that a blow over the head will give a sensation of light, vibrations l/Hng set up and transmitted to the brain.