The Bioscope (Jul-Sep 1931)

THE BIOSCOPE MODERN CINEMA TECHNIQUE vm HORIZONTAL ARC 1 9°*' 9 ate 7 m/m . lOrnjrv Cofbon 4 Q m/m crater '«} 9m/m ]2m]rr\+ cations . — . \ 6-5 m/m crater \ I I } economic focus uneconomic focus £ ~~1 c/ote 10 mfm1 Q-m]m+ carbons / — . \ 9m/m crater \ 1 — I ; wasteful focus fig. n conditions obtaining, therefore, it has been necessary to provide a small diameter of positive in order to obtain the necessary intensity from the current available in installations. A small positive implies a negative smaller still, and it is when dealing with these small carbons of 5 and 6 mm. overall diameter that the inserting of cores and the maintenance of strict proportions in the respective thicknesses of shell, core and copper coating become matters which call for something little short of wizardry. Another consideration is, of course, the burning rate of such small carbons. Naturally for a given current a small diameter carbon will burn more rapidly than one of larger diameter. The Hilo Positive is made in lengths of 8 and also 12 inches, and these lengths will be found to meet all requirements satisfactorily. But I should like to mention that it is unwise to insert these carbons in the holders so that contact is made nearly half way down the length of the rod. It is true that this does something to emulate the high intensity forward contact and that it increases the current density at September 30, 1931 the crater, but the trouble is likely to come in when you find that you have to loosen the jaws in the middle of a run and attempt to tap the rest of the carbon through, while at the same time maintaining correct gap and focus. The positive is copper-coated for the purpose and will carry all the current necessary to give a brilliant light, even when the carbon is held correctly in the jaws at its far end. Next week I hope to deal with the behaviour of the Hilo carbons in the arc, and to give some consideration to the question of magnetic flame control. Playhouse, Northwood, Modernised The Playhouse Cinema, Northwood, Middlesex, which was recently acquired by A. Dove, has now been reopened, following a complete remodemisation and redecoration scheme. It is now said to be the most up-to-date cinema in the district. Amongst the new amenities was the inclusion of a talking equipment, B.T.-H. being the system selected. The control of the theatre will be in the capable hands of the proprietor, who is very well known in London entertainment circles by reason of the fact that for over 20 years he was musical director at the London Coliseum for Sir Owsald Stoll, and only relinquished that post early this year. Exmouth Plans Passed Exmouth magistrates have approved plans presented on behalf of C. H. Palmer for a new cinema at the Manor Hall, Exmouth NATIONAL ECONOMY Achieve ECONOMY by purchasing the CHEAPEST, consistent with EFFICIENCY. Foster the NATIONAL SPIRIT by purchasing BRITISH MADE GOODS. \\xT 1 N a progressive world the man is successful who 1 keeps abreast of progress. To-day a higher standard is set, and what is more important, is expected in advertising. The modern advertisement must be artistic, appealing and simple in operation. The B.B.T. range fulfills all these requirements. B.B.T. SPECIAL D.C. SHEETS and B.B.T. INTERCHANGE Both these objects are attained by installing the ROTH SOUND-ON-FILM ABLE SIGNS will modernise your lobby display. Let us send you full details. System in your Theatre ^ ^ Ltd, COMPLETE EQUIPMENTS FROM £245 HIGH H0LB0RN HOUSE, LONDON, W.C.l Scottish Agents: Telephone: Chancery 7964 STEWART & NEIL, 93, Hope Street, Glasgow. C.2 ROTH EQUIPMENTS (GT. BRITAIN) LTD. Telephone: Central 5998 FILMATINE HOUSE, 1 24, DENMARK STREET, LONDON, W.C-2