International projectionist (Jan-Dec 1936)

32 INTERNATIONAL PROJECTIONIST December 1936 ^ ^DELUXE 40 WATT THEATRE AMPLIFIER '>Ak>\ 'T'HE LAFAYETTE Model 400A is designed speci-*■ fically for theatre use, with exceptionally rugged parts for failure-proof operation. It has ample power for theatres and auditoriums seating 3,000 people. All controls are mounted on the face of the amplifier; fuses and tubes are easily accessible. Microphone circuit permits stage announcements and music from a non-synchronous source. MODEL 400A— Lafayette 40 Watt Theatre Amplifier, less tubes. Panel for standard rack mounting. 110 Volts A.C. Code ASTAN. YOUR COST $68.50 KIT OF TUBES 5.24 9.75 W22086— Black Metal Cabinet for wall mounting . . . MAIL THIS COUPON FOR; CATALOG Wholesale Radio Service Co., Inc. 100 Sixth Ave., New York, N. Y. Please send FREE Catalog |6SM77. State . . All New Announcing . . . „, "•*?*« O Clayton lake-Lips For all projectors and sound equipments All take-ups wind film on 2, 4 or 5 inch hub reels. The Clayton Rewinder For perfect rewinding on 2000-foot reels. CLAYTON PRODUCTS CO. 31-45 Tibbetr Avenue New York, N. Y. pressure. The nozzle is so designed that it breaks up the stream of water into a very fine spray, which is ejected at high velocity. It is possible that further developments in the use of highpressure sprays may he of value and importance to the motion picture industry. Water applied to fire under such conditions seems to be considerably more effective than when thrown from a sprinkler system, hose, or extinguisher. Such a spray has a great cooling effect. The fine spray cools the surrounding atmosphere, and is most effective in preventing the spread of fire. It has also the property of washing out obnoxious fumes and gases given off by burning or decomposing nitrocellulose film or other material. One of the large sprinkler companies made some tests for the writer with these spray nozzles on burning film, and, as a result, it was felt that they merited further consideration and study. With the spray in operation, a reel of motion picture film rea sonably isolated can be completely consumed by fire with little, if any, possibility that the fire will be communicated to nearby film or equipment, with the fumes reduced to a minimum and with the temperature of the room kept at a normal degree. Fighting Oil Fires Burning oils afford a somewhat difficult problem. We do not have much success in extinguishing oil fires with water. Unfortunately, oil is lighter than water, and water from hose streams or sprinkler systems used on oil sinks to the bottom and may cause the oil to rise and overflow. The spray method, however, depends for its effectiveness upon the fine globules of water penetrating the oil for a short distance and forming an emulsion of oil and water at the surface of the oil. This emulsion contains a sufficiently high percentage of moisture to be non-combustible, and there is thus formed a non-combustible blanket over the surface of the liquid. In addition, the water has a cooling effect, and the stream produced excludes oxygen. An automatic sprinkler system is the best all-around fire fighting device. Automatic sprinklers have behind them a record of many years of effectiveness in fires of all kinds. Studios, laboratories, vaults, exchanges, and all rooms wherein film is handled . and stored should be equipped with automatic sprinklers. The hazard to life is practically eliminated in sprinkled buildings. The spray from sprinklers has a great cooling effect, and washes out smoke and obnoxious gases given off by the burning materials. The requirements for maintenance are highly technical and space does not permit covering them here. Persons should not be subjected to the fumes of burning film unless equipped with a mask. It may be interesting lo know that until recently no tests had been made to determine the effectiveness of the canister type of mask in film fires. The U. S. Bureau of Mines has, however, made such tests, and has found that the BurrellAll-Service mask is safe for such use. The oxygen helmet is also effective, but is cumbersome to use. Several pairs of asbestos gloves are kept near the sound equipment, to be used for beating out small fires or handling hot wiring or other parts at time of fire. We have experimented with various fire extinguishers, and after considering all factors have adopted the carbon dioxide type. This type discharges a large volume of carbon dioxide gas at extremely low temperature. Carbon dioxide will not sustain combustion and, therefore, serves to blanket the fire out. Distilled water in a pump type of extinguisher, or an extinguisher using a cartridge filled with gas at high pressure, may be used as a second line of defense. However, prevention of fires is far better than extinguishing them, and engineers engaged in the design, construction, and maintenance of sound equipment should give the utmost consideration to prevention of fire. Non-combustible materials and insulation should be selected whenever it is within reason to do so. Capacity of conductors should be adequate. Avoid too large values in any one unit. Design should call for segregation in rooms of fire-resistive construction, divided into comparatively small sections and equipped with every modern fire-detecting and fire-extinguishing device. The room should also be waterproofed not only against leakage but against rising water. Fire protection is a special art and it is asking too much to expect the motion