836 



Popular Science Monthly 



Six Acres of 



O' 



Washing the negatives in clear water after the develop- 

 ing and fixing process. Two-hundred-foot lengths are 

 handled at one time and afterward pieced together 



film an additional bath is required to clear 

 the high lights and sharpen the detail; 

 otherwise the method is the same as for 

 the negative. 



The two-hundred-foot lengths of film 

 are then wound on reels, five lengths being 

 cemented together to produce the standard 

 length of one thousand feet. 



In every picture "titles" and "sub- 

 titles" are required to explain the action. 

 These are photographed on the film when 

 the other parts of the picture have been 

 taken. The piecing together of the vari- 

 ous sections of film requires the exercise 

 of great care for never are the scenes of a 

 play filmed 

 from begin- 

 ning to end 

 exactly as 

 they are 

 planned by 

 the scenario 

 writer. If 

 five different 

 episodes take 

 place in 

 a d rawin g 

 room, they 

 will all be 

 photographed 

 at once, even 

 though hun- 

 dreds of feet 

 of landscape 

 film may ulti- 

 mately in- 

 tervene be- 

 tween them. 



A typical coal boat. It is twenty-six feet wide and 

 travels abreast of eleven others and a steamer 



Coal Floating 

 on the Mississippi 



NLY in the United States can 

 such a sight be seen as six 

 acres of coal floating down a river 

 as a single unit. This is the area 

 of coal boats which the well- 

 known stern-wheel steamer 

 Sprague is capable of handling as 

 a single tow. Four across-stream 

 rows of twelve boats each, make 

 up the principal part. Back of the 

 fourth row, however, eight boats 

 find places together with two 

 barges. Hence, there are fifty-six 

 boats and two barges in the big 

 fleet. The Sprague has her nose 

 shoved in at the center of the 

 fifth row. The fifty-nine vessels 

 are lashed securely together by 

 lines which run from boat to boat. Al- 

 though the Sprague can push the fleet 

 ahead, her chief duty is to hold back the 

 load. 



This great amount of coal is handled by a 

 relatively small total of horsepower because 

 the current of the onflowing river supplies 

 a large part of the requisite energy. 



The big efficient stern wheel of the 

 Sprague stands forty feet high. When 

 bends in the river have to be rounded, it 

 controls the boats by suitable backing move- 

 ments. If the steamer itself goes aground, 

 this big stern wheel ma}^ be utilized to 

 drive water in under the stern of the 



boat to sup- 

 ply a kind 

 of miniature 

 flood tide. 

 When the 

 sand bars, 

 swift current 

 and tortuous 

 course down 

 the Missis- 

 sippi River, 

 where the 

 Sprague is 

 principally 

 engaged, are 

 taken into 

 consi dera- 

 tion, it will be 

 granted per- 

 haps that the 

 captain has a 

 responsible, 

 difficult task. 



