CH. XI] MOVING PICTURE EXHIBITION 433 



paper would be. The end of the film did not get as hot as that 

 projecting from the upper magazine because the rising flames did 

 not tend to play around the unburned part. It would seem, there- 

 fore, that the fire would probably not be carried into the lower 

 magazine along with the film. Of course, with the upper magazine 

 the film is going out of the opening in normal operation. What 

 would be the effect of the sharp blaze from a meter or more (three 

 feet) of loose film which would quickly unwind if the film broke can 

 only be conjectured. It would be likely to get the magazine red 

 hot and set the film inside on fire. 



With these possibilities of risk in mind, one will naturally be very 

 careful in handling the apparatus, so that nothing shall start to 

 burn and to follow the precautions of keeping all of the films not 

 in use inside of fire-proof boxes. The two films in use are : the film 

 in the machine, and the film which has just been run through and is 

 being rewound. 



When non-inflammable film is used the above precautions are not 

 necessary from the standpoint of fire risk, but the films might be 

 spoiled. It is, however, a good plan to be careful even if non- 

 inflammable films are used, so that habits of carelessness will not 

 lead to accident should one of the celluloid films be included with- 

 out the knowledge of its nature. 



THE CONDUCT OF AN EXHIBITION 



597. Inspection of the plant. Is the exhibition going to go 

 smoothly, without hitches, or will the light be poor and go out, the 

 film be out of focus, and break and everything go wrong? This 

 depends largely upon the operator and a very careful inspection of 

 all the apparatus before the exhibition begins. 



The principle things to look out for are: 



(1) See that all wiring is in good shape, no binding posts loose, 

 no wires almost burned out in the lamp. 



(2) See that the carbons in the lamp are long enough, that extra 

 carbons are ready, that tools to change carbons are handy. 



(3) Burn the arc a little while till the carbon ends are properly 

 shaped. 



