YOUNG FARMERS

Evening Star, Issue 21753, 22 June 1934, Page 5

YOUNG FARMERS

EDUCATIONAL AND CULTURAL COURSE “ WAVES OF MANY KINDS " At the Otago University yesterday afternoon the young farmers who are taking advantage of this week’s educational and cultural course in the city were addressed by Dr 11. Jack (professor of physics), who, for their benefit, repeated the absorbing lecture and demonstration which he has previously given on * Waves of Many Kinds. Dr Jack described in simple and illuminating words the peculiarities ol water waves (as when a stone is thrown into water), light waves, wireless waves, sound waves, and electric waves. A water wave, he explained, was called a transverse wave, because the particles of water were moving up and down, although the rest was moving along. Sound waves, on the otlici hand, were longitudinal, in wireless the .distance from crest to crest was one wave length, and in Dunedin the distance from crest to creet of the wireless waves sent out was about 400yds. “ We have other waves far shorter,” Dr Jack said. “The length of a blue light wave, for instance, is only one fifty-thousandth of an inch, while there are others shorter than that.”

The term “ frequency ” was also explained by Dr Jack, who said that a low note produced few waves, while with a high note the number was increased, so that the pitch of a note depended on its frequency—the number of vibrations a second. The speaker then gave a number of demonstrations comprising experiments in sound. Setting up a vibration in a couple of organ pipes he made certain combinations of sound, and explained the reason for certain changes in the pitch. He also caused small gas flames to sing on a high note in glass tubes, hut his most interesting demonstration, and certainly the most spectacular, was doue by means of an instrument resembling a square box with a small lamp face in it. A switch was pressed, and across the glass face glowed a thin green: horizontal tube of light, like a pencil. Dr Jack then spoke into a mouthpiece, and the light twisted and danced furiously all the time he was speaking, contorting itself into strange designs and jumping up and down continually. This was caused by the sound waves from the speaker’s voice, the light reacting to each wave as it struck it. A reed instrument was blown into the mouthpiece; and it was seen that the movements, while just as excited, were sharper in outline. This instrument has many uses to science, and can be used in studying heartbeats, any change being instantly recorded. One of Dr Jack’s students, speaking into an ordinary ■ radio amplifier acting in reverse, made a gramophone record of his own voice with which he was able to demonstrate immediately afterwards., , . ' An X-ray demonstration followed, Dr Jack explaining that all that was don© was to send little electric par-, tides up against a plate, and out of that plate came the X-rays. He held up a purse, and its contents were dimly seen, as also were the contents of a wooden box. “ Some students try putting their heads there,” Dr Jack said with a smile, “ but sometimes their heads are too dense.” Colour and light vibrations were also dealt with, and Dr Jack showed how, by directing certain rays from a lantern on to a bunch of flowers, their original colour_ was superseded by another combination of colours. Illustrations of vibration were also given by means of a machine which vibrated a length of string and also by means of a rubber flex stretched across the room which Dr Jack agitated, and on which the waves could be clearly seen as they moved backwards and forwards. ... , Dr Jack concluded his address by pointing out that these experiments served to show that by understanding natural phenomena they could find a great deal of interest in what they saw around them. A very cordial vote of thanks was moved by Mr Tan Dallas (Balchitha).

FURTHER ATTRACTIONS VISIT TO ‘ EVENING STAR ' AND 4YA After attending i)r Jack's lecture the party proceeded to the ‘ Evening Star office, where they were welcomed by the managing director (Mr C. Stanley Smith) and several other directors of the firm. “ The initial rendezvous was the machine room, which houses the big rotary printing press. Here the lads became very much interested in seeing the evening paper going through the last stages of its production, the fact that the press was printing, folding, and counting 500 newspapers per minute being the subject of much enthusiastic comment. Subsequently a flashlight photograph was taken, and the visitors were divided into four parties, each under a guide, for the purpose of being shown various other processes associated with the work of the company. All were given an opportunity to inspect the 160 h.p. Diesel engine and electric generator which are used to drive the machines and illuminate the entire building, as well as to supply all power in a case of emergency. The jobbing department, the box factory, and the plate-casting machine were also seen, the young men paying eager attention to everything they saw. Through the courtesy of Mr H. Ninnis (station director of 4YA) the visitors, section by section, were _ also shown through the well-appointed studios in the adjacent premises. Here again they displayed the keenest interest in every aspect of the matters explained tb them, many of them no doubt satisfying a very natural curiosity as to the methods of broadcasting the entertainments which they hear in their own homes. At the conclusion Mr Boyd Rapson (Ngapara) moved a very hearty vote of thanks to the management of the ' ‘ Evening Star ’ and the broadcasting station for their kindness in making the visit possible.

SOCIAL GATHERING PRESENTATION TO OFFICIALS Last evening the Otago Farmers’ Union Mutual Fire Insurance Association tendered the young farmers a social which was held in the Tudor Hall at the Savoy. There was a large gathering, and the function proved one of the most successful of the week. The chair was occupied by Mr A. B. Strothers (Farm Accountancy Association). During the evening opportunity was taken to make presentations to three of the officials—Messrs A. G. Cameron (.genera! manager of Iho Otago Farmers’ Mutual iusuiaiico Association and organiser, of the .Young Farmers’

Week), C. F. Jones (secretary for | Otago of the Young Farmers’ Club | movement), and S. D. Blomfield (gen-j eral secretary for New Zealand of the movement). Messrs *l. Clearwater (Palmerston), A. Paimett (Clydevale), and A. T. Heckler (Waikouaiti) made the presentations, and each spoko briefly, referring to the excellent work done by the recipients for the movement in New Zealand, and in Otago. Mr Cameron was given a travelling rug, Mr Jones a safetyrazor, and Mr Blomfield a pipe. The recipients suitably returned thanks. Mr M. A. Kinney (Hyde), president of the Otago Farmers’ Union, who was introduced by Mr Cameron, spoke of the good work which was being done by the movement, and on behalf of the Farmers’ Union he thanked all concerned with the educational week for their efforts oi\ behalf of the boys. An enjoyable programme was presented, songs being rendered by Mr and Mrs J E. Davies (Dunedin), Messrs Howard Sutton (Moa Flat), J- Becker (Oturehua), William Kane (Becks), and A. B. Struthers (Dunedin), and recitations being given by Miss IM‘Gregor and Mr C. F. Jones (Dunedin). Orchestral items were provided bv a party organised by Mr E. S. Thomas, of the Mutual Insurance staff. Very spirited community singing wasj conducted by Messrs J. E. Davies and A. B. Struthers, and Mr H. Eggers was responsible for some amusing feats of ventriloquism. During supper the toast of “ The Ladies ” was proposed by Mr C. F. Jones, supported by Mr Boyce Rapson and Mr A. Allison, and was replied to by Mrs J. F. Drake and | Mrs James Begg.