The Moving Picture World (April 1907)

122 THE MOVING PICTURE WORLD. Conversation Heard in the Office of a Dealer in Motion Picture Machines. Customer: I called in reference to purchaing a pro- jection machine. I do not know the first thing regarding same and wish to be instructed in its manipulation, etc What is really necessary to operate one of these ma- chines? Dealer: It does not require over-intelligence; but a person intending to go into this business must certainly' have a little gift of mechanical ability to master it suc- cessfully. C.: But, as I say, I have never used one of these ma- chines, and you say it requires a little mechanical ability, and not being a median: ?, what difficulty have I to over- come? D.: The difficulty is "very slight, depending upon the interest shown and acumen of the purchaser. C: What length of time would be required to thor- oughly understand the operation of the instrument? D.: We have had buyers who have been capable of giving a successful public exhibition after being instruct- ed once in the feed of the machine and the focusing of the light. The man of average intelligence after three or four private trials can successfully give his first pub- lic exhibition. C.: You made a remark a moment ago about "feed- ing" a machine. What do you mean? D.: "Feeding" is simply a term used in the trade for threading the mechanism; properly adjusting the film. C: What do you mean by proper adjustments? D.: Placing the film under the feed sprocket; being careful to fit the perforation of the film into the teeth of the sprocket and fitting the rollers over the sprockets and allowing proper tension on the loops. C.: How am I to know whether the machine is prop- erly threaded? D.: By taking the film between the thumb and forefin- ger and allowing a loop which would comfortably wrap around your thumb, on the top and bottom sprockets, which allows play for framing the picture. C: What do you allude to by "framing"? D.: The pictures are spaced about three-fourths of an inch; and at times two pictures, or the line of two pict- ures, enters the centre of the aperture and projects the bottom of one and the top of the following picture on the sheet It is therefore necessary to frame the pict- ure, with the use of this lever, so as to bring one com- plete picture on the screen at one time. C: Where is the aperture located? D.: About midway in the mechanism. C.: Where does the film feed from? D.: From a reel upon which it is wound, which you see here, supported on the top of the mechanism. C.: I propose using this machine if I can operate it perfectly, at a church in which I am interested. What difficulties will I have to overcome before I cangi public exhibition? What is absolutely necessary far to have? D.: It depends upon circumstances. Where is church located? C: In New York City. D.: In that case it will be necessary for you to by the regulations of the Fire Underwriters top with those of the local authorities. The restrictions pel the use of a magazine underneath lower sprocket, above the top sprocket. The lower magazine requii take-up device. C: What do you mean by a take-up device? D.: It is this device which rewinds the film as it through the mechanism after being projected, as si here. As mentioned before, the Underwriters are particular regarding the construction of the lampi as well as the electric lamp. The same must be to meet their entire- approval, which necessitates the of a lamphouse made of Russia iron which encloses light. The roof of the same has an extended top perforated metal for ventilation, and the entire roof is ered with sheet mica, so that a carbon cannot coo contact with the metal parts of the lamphouse; would cause a short-circuit if this precaution was taken. C: You speak here of carbons arid electricity, d obliged to have that? D.: No, you are not. If you prefer, you can nst oxy-hydrogen light. C.: Can I obtain as good results with oxy-hydrogi with electricity? Which, in your opinion, is the illuminant? D.: Electric light, by all means, if direct current be obtained. C.: Not being conversant with electricity, how sh best apply the oxy-hydrogen? D.: I can show you that in a very few moments. can see this is a calcium burner. We place a limeii cup, and allow the lime to turn freely on the sere revolve one-eighth of an inch in front of the tip. place the burner in the lamphouse, on, the same pc you would use for the electric lamp. Attach the to the burner, and the tanks. Calcium cylinders are ed red and black. The black tank representing the drogen, and the red, oxygen. We set the burner so that the tip is nearly in thee of our condensers, setting about three inches away i same. Open the black cylinder first, allowing sufficieBt to flow through the burner. Now light the same- now have the hydrogen burning, and we next op« oxygen, or red tank, very slowly. Now you see ta suits. Our light is perfectly white, giving us a brffl iflurnination. We have a black circle on the bottom. therefore lower our burner slightly and the lower circle is removed; but we wish now to still increas