438 



DO AND DO NOT WITH MOVING PICTURES [Cn. XI 



599 1 . Summary of Chapter XI: 



Do 



1. Learn the principles, and 

 perfect yourself in the practice 

 under expert guidance, before 

 you assume the responsibility of 

 an independent operator. 



2 . Keep your operating room 

 in perfect order. 



3. Light the theater so that 

 the lights cannot shine directly 

 in the eyes of the spectators or 

 upon the screen. 



4. Have a perfect screen. If 

 it is a painted screen, add a fresh 

 coat occasionally. 



5. Use direct current for the 

 arc lamp if possible (Ch. XIII). 



6. Inspect wiring and appara- 

 tus daily. 



7. Keep the lenses of the con- 

 denser and of the objective 

 clean, and in the right relative 

 position. 



8. Keep in mind the precau- 

 tions ( 593-594). 



9. Leairn to conduct the ex- 

 hibition in the best possible 

 manner. 



10. Remember that it is far 

 easier to avoid a fire than to put 

 it out. 



Do NOT 



1. Do not pretend to be a 

 competent operator until you 

 have the requisite knowledge 

 and experience, and then never 

 stop learning. 



2. Do not have your operat- 

 ing room in disorder. 



3. Do not install room lights 

 so that they can glare in the 

 eyes of the spectators or shine 

 on the screen. 



4. Do not project on a dirty 

 screen. 



5. Do not use alternating 

 current for projection if you 

 can use direct. 



6. Do not neglect a careful 

 daily inspection of wiring and 

 apparatus. 



7. Do not use dirty lenses or 

 objectives. 



8. Do not fail to study care- 

 fully the precautions ( 593). 



9. Do not neglect the direc- 

 tions for the conduct of an 

 exhibition. 



10. Never forget the danger 

 from fire. 



