Photographing Sunken Ships 



A giant electric camera is used for 

 locating sunken ships and treasures 



AN electric submarine camera for deep 

 sea photography has been invented 

 by H. Hartman, a civil engineer of 

 New York city. With 

 it a sunken submarine or 

 a wrecked vessel may be 

 located and pictures of 

 its condition projected 

 for study on a screen in 

 a few hours. Experi- 

 enced divers would re- 

 quire days to secure the 

 same information. 



The camera consists of 

 several cylinders con- 

 nected with a steel frame- 

 work. The ball at the 

 bottom is a shock ab- 

 sorber, and the compart- 

 ment above it contains a 

 gyroscope to steady the 

 apparatus against vibra- 

 tion. In the top cylinder 

 is a motor which turns a 

 propeller. This rotates 

 the camera up on its 

 vertical axis so that pic- 

 tures can be taken in all 

 directions. Current for 

 the motor is obtained 

 from above through a 

 cable. 



The tank below the 

 propeller cylinder con- 

 tains the camera, as well 

 as the tilting, swinging 

 and focusing apparatus. 

 The shutter and focusing 

 mechanism are both op- 

 erated from separate 

 switches on the surface vessel. A third 

 switch enables the operator to swing the 

 camera in conjunction with the light pro- 

 jector or independently of it. Tests carried 

 out aboard the U. S. S. Vestal proved that 

 the camera could take pictures of the same 

 object repeatedly. Although some were 

 out of focus, the majority were sharp and 

 clear. 



Concerning the source of light, which is 

 contained in the largest cylinder of the 

 apparatus, very little is known. Current 

 for the light comes from the surface through 

 a special cable. According to the inventor 



The camera is lowered in the 

 water to any depth up to one 

 thousand feet. The pictures are 

 taken and the entire camera 

 mechanism operated from the 

 surface by means of switches 



the light projector consists of a strong 

 steel cylinder, filled with a gas under 

 varying pressure and having highly con- 

 centrated filaments. The 

 light works on the prin- 

 ciple of the ordinary in- 

 candescent bulb, so far 

 as is known. An inner 

 circle of transparent mica 

 protects the heavy glass 

 lens from the intense 

 heat, although the sur- 

 rounding water reduces 

 the temperature consid- 

 erably. A valve mechan- 

 ism varies the pressure 

 of the gas according to 

 the pressure of the water 

 in which the cylinder is 

 submerged. Reserve gas 

 is contained in a separate 

 compartment. In addi- 

 tion to the live wire 

 which acts as the source 

 of light, there is a flexible 

 steel wire rope to carry 

 the weight of the entire 

 apparatus. 



On land the camera 

 mechanism weighs one 

 thousand five hundred 

 pounds. Submerged it 

 weighs about one hun- 

 dred pounds. All parts 

 are tested for a pressure 

 of five hundred pounds 

 to the square inch, which 

 corresponds to a depth of 

 about one thousand feet 

 of water. To operate the 

 light projector and the several small motors, 

 a current of approximately one hundred 

 amperes and one hundred and twenty to 

 one hundred and forty volts is required. 

 When the camera is operating at a great 

 depth under water, the voltage has to be 

 increased to two hundred to make good 

 the loss in passing through the long cable. 

 The inventor proposes to use his camera 

 for treasure hunting, for the locating of 

 sunken ships, and for the study of marine 

 growths. There is no question but what 

 the camera will be of great value in wreck- 

 ing and salvaging operations. 



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