The Science Society

President: E. K. ROBINSON, EsQ., B.Sc. Hon. Secretary: R. J. GIBSON. Hon. Treasurer: M. A. CROSS.

Five meetings on varied topics were held this term. The first was on 25th September, when a lecture on photography was given by Mr. Thos. H. Mason, an exhibition of whose photographs was held at the end of the previous term. After giving some advice for taking photographs he projected on the screen some slides taken by himself, most of which were in Kodachrome. He had some very beautiful photographs, including some of the Lake District, Scotland, Knaresborough, Barnard Castle, Dartmouth, Kirkham Abbey, Torquay, and some very good ones of the "Moorlands", a pleasant garden stretch just outside York. He included several slides in which he had made mistakes, pointing them out. His last five photographs were of York itself. Questions were asked during the lecture and at the end. Mr. Robinson was in the chair.

The second lecture, on 9th October, entitled "Aeronautics", was given by Mr. Harris. He described how experiments were made in wind tunnels, and went on to explain about aerofoils, the cross sections of the wing. He described how if flaps and slots are used a greater angle of attack can be obtained without the plane stalling, and by means of the epidiascope showed several graphs to illustrate lift and drag, and the angle of attack for different aerofoils. He described how a plane landed, and how planes looped the loop, went into spins, and turned by banking. He also told us about the three axes of the plane, about which it could turn by movement of the ailerons, elevators and rudder. The talk was illustrated with the epidiascope, and by a model. Questions were asked at the end. There was a large attendance, and Mr. Crews was chairman.

The business meeting was held at the end of Mr. Harris' lecture. A senior, a middle, and a junior representative from each House were elected on to the Committee. The treasurer and secretary were re-elected.

The third meeting was held on 23rd October. Three films were shown entitled : "Roots", "Civil Engineering", and "The Story of Ceylon". The first film showed the growth of the root from the embryo. The sensitive tip could clearly be seen. The growth of the root hairs, etc., were also shown. The second film, "Civil Engineering", described the many tasks under civil engineering, and explained how a power station is built from the surveying of the site to the finished building. The third and last film, "The Story of Ceylon", was about Ceylon from early days to the present day, showing the life of the people, their religion, and their ceremonial dances. Weird Eastern music accompanied the film throughout.

On 27th November Mr. J. E. Collins, the chief engineer at the G.P.O., gave an illustrated lecture with demonstrations entitled "Telecommunications". Mr. Pallier, his assistant, worked the epidiascope. He introduced his talk by describing how the telephone transmitter and receiver and their complications worked. With the help of pictures from the epidiascope Mr. Collins showed us both types of exchanges, and described in detail how an automatic exchange works. Mr. Collins also described frequencies and the coaxial cable. Questions were asked at the end, and Mr. Pallier, who had brought along a model automatic telephone exchange, constructed by himself, demonstrated it with two telephones. Mr. Robinson was in the chair.

The last meeting of term was held on 1 1 th December, when Mr. Le Tocq gave a lecture on "Soil Erosion". We were to have had two films as well, but these did not arrive, and we appreciate Mr. Le Tocq's willingness to fill the breach so well at such short notice. He described the different types of erosion, particularly in the U.S.A., emphasised its seriousness, and explained the causes and the cures.

A VISIT TO A CHOCOLATE FACTORY

On 17th November a visit was paid by sixteen boys, representing the Science Society, to the Bishopthorpe Road factory of Messrs. Joseph Terry & Sons, Ltd. The arrangements were made by Mr. Noel Terry, a Governor of the School, and to him we are very grateful. The group of visitors was welcomed by the firm's chief chemist, Mr. Marston, who first of all gave us an introductory talk about the manufacture of chocolate.

The firm imports cocoa beans from Africa, the West Indies, Samoa and Venezuela, where the very best beans are grown. The cocoa beans grow in red or yellow pods, which hang from the trunk of the cocoa tree. The beans are heaped up and fermented, dried, and put into sacks. Terry's blend different varieties of beans to obtain the finest flavour obtainable. In addition, vanilla pods are imported, for vanilla flavouring is the base upon which the flavour of chocolate is built. Vanilla pods are long and slim, and are fermented just like the cocoa beans. After storing, a mass of white needle crystals can be seen on the pods; this is "Vanillin". Vanillin can be made synthetically, but the firm prefers to use the natural product, as the flavour is superior to that of artificial vanillin, the former being accompanied by other flavours. The cocoa beans contain about 50 per cent fat, or "cocoa butter". This is used in the manufacture of chocolate, but as this percentage is insufficient to make good chocolate, a quantity of the beans is crushed and the fat is extracted and later on is mixed into the chocolate.

After this talk, Mr. Marston took us to see the whole process for ourselves. The beans, dried and cleaned, are first roasted in gasheated hot-air oven to about 250 degrees F. The beans are then

cooled and husked, the residue being known as "nibs". The nibs are then ground very finely so that the cocoa butter is crushed out, and the product is a very smooth liquid, which to our untutored eyes was as smooth as possible. We had a lot to see, however, before the chefs were satisfied ! This smooth liquid is then mixed with sugar powder and refined several times in special machines, and the product is often tested microscopically to ensure its being fine enough.

The superfine powder is mixed with cocoa butter and ground again in machines called "melangeurs". Finally, the liquid is mixed in a machine called a "conche" for several days until the grains are smoothed to a homogeneous texture. Our guide regretted that milk chocolate production is temporarily suspended, the firm's herds of cows giving their milk to the Milk Pool. The plain chocolate is cooled in vast ammonia refrigerators and stored in 56 lb. blocks until it is wanted.

As we were to view the production of fancy chocolates, we were taken into the main block of the factory. This is half as long and half as wide as the "Queen Mary". On the roof stands the air-conditioning plant, which makes the air admitted to the block a uniform temperature of 65 degrees F. and a relative humidity of 55 per cent, which is best for the workers and the chocolate.

The top floor is devoted to the making of the different centres. We saw and smelt caramels, fondants, coffee cream, almond, nut, fruit, gingers and fudges being made. Tearing ourselves away we inspected the apparatus for making glace cherries and fondant cream. This cream is really a paste of very fine crystals of sugars and glucose.

In the next department the liquid centres are cast into ingenious starch moulds. Next door, we came to the covering department, where the raw chocolate is flavoured and mixed with the final amount of cocoa butter. First of all the 56 lb. blocks are melted in a large oven, and then the hot yellow fat is mixed in. The different centres are placed on conveyor belts which deposit them on a perforated drum, which ingeniously coats the bottom of the centres. Each belt then takes the centres over a super-cooled section, where the chocolate sets, and into the covering machine, which pours chocolate over them. The chocolates pass on over embossed papers, which stamp "Terry" underneath. At the same time the chocolates are ornamented on top. The belt carries the chocolates to the cooling department, where they are set in trays.

When the chocolates are set they are weighed and sent to the packing department. Here certain lines of chocolate are wrapped in silver papers by an ingenious system of mechanical fingers. The chocolates are finally placed in trays at the ends of the packing lines, each tray holding one type of chocolate. The chocolates are packed in cartons by girls and women, who between them pack some 4,000 each day, each box taking only seconds to assemble. A packer takes 34