Kinematograph Year Book 1942 (1942)

Film Exhibition and Kinema Technique 227 this supply is used for charging purposes. By this means the cost of the equipment is kept down to a minimum. One knob control is again used here, having four positions, as follows : — (i) Equipment out of action ; (ii) Ready for emergency ; (hi) Charge and emergency ; (iv) Charge only. THE INDEPENDENT PLANT. THE reserve of service available to the possessor of an independent plant has proved of undoubted value to the exhibitor under war conditions because, while not ignoring the urgent demand for the most stringent economy in the use of fuel, he is secure in the knowledge of independence of the effects arising from a sudden failure in the mains supply which, not only may conceivably cause a loss of valuable revenue over a period, but may also interfere with the provision of entertainment in circumstances where it is most desirable. Many instances have occurred where a considerable period has elapsed following air raids before the electricity service has been restored. A further inducement for the installation of independent plant is the undoubted economies which can be effected at a time when the cost of current from supply undertakings is following the general upward curve in commodity prices. True, in some cases the basis of the advanced charges has been adjusted in view of war conditions, but, generally speaking, little consideration has been given to the fact that only a very small proportion of lights are allowed as compared with that time when existing standing electricty charges were originally fixed. When it is appreciated that current can be generated by a diesel engine at a cost varying from 20 per cent, to 50 per cent, lower than the mains supply charges, the advantages of an independent plant are apparent, although it is doubtful whether manufacturers are now in a position to cope with orders except for forward delivery. The subject, however, is one which should figure in any arrangements being contemplated in an exhibitor's post-war plans. The reliability of these power units is testified to by the large numbers which, in normal circumstances would have been scrapped, are being continued in service, and this knowledge may suggest the obtaining of a second-hand plant. If so, a once-over by, preferably the maker's engineer, should be insisted upon and an assurance as to the availability of supplies is an essential precaution. The question of fuel supplies and storage facilities has also to be considered. The price of the former has, of course, advanced, but it still compares favourably with the mains charges, and although the question of the amount and continuity of suoplies is obviously of immense importance in current circumstances, at the time of writing there appears little reason to imagine insuperable difficulties in this direction, although anxiety is understandable. In this connection, the possibilities of a gas-operated plant should be examined, although during war-time damage to the gas mains may precipitate those consequences which the installation was intended to avoid. On the other hand, an advantage is that the fuel is indigenous, and for the moment, uncontrolled, and in addition is one for which the majority of gas undertakings are prepared to quote low rates for power purposes. The full benefits of an independent prime mover are derived under normal conditions which enable the exhibitor vastly to improve the margin between his own costs and the mains supply charges for not only need he discount the possibility of a supply breakdown, but, at very little appreciable increase in costs, he is able to supply current for the most ambitious decorative and publicity schemes as well as his utility and exterior illumination. The outlay is confined to his first charges, of purchase and installation, and where necessary, the engine-room ; beyond these, the outlay is inconsiderable, for little maintenance is involved, and the attention demanded amounts to little more than occasional efficient supervision. H z