Taking Photographs From a 

 Skyrocket 



AMONG the aids to the conduct of 

 /-\ the war that have been proposed in 

 Germany is the photography of the 

 enemy's positions by the flight of rockets 

 carrying cameras. The invention is less 

 expensive and can be sent up closer to 

 the enemy without provoking attack 

 than a captive balloon, dirigible or aero- 

 plane. Besides, it is not so dependent 

 upon the wind a§ a kite. 



When the inventor, Alfred Maul, be- 

 gan his experiments fifteen years ago, 

 he found, as he tells us in an article ap- 

 pearing in Umschau, that the ordinary 

 rocket can hardly carry a considerable 

 weight, and so he 



View of a German town taken with 

 rocket from a height of 1,550 feet 



was obliged to de 

 vise one of greater 

 strength. 



His first inven- 

 tion was a shell 

 closed above and 

 open below con- 

 taining a firmly 

 compressed pow- 

 der composition in 

 which was a deep 

 opening. Ignition 

 dev^eloped a con- 

 siderable volume of 

 gas, w^hich gas 

 pressed down upon 

 the atmospheric 

 air, thus causing 



the rocket to rise. In a shot the initial 

 velocity is the highest, whereas in the 

 rocket the initial velocity is low but in- 

 creases until the charge is burnt out. 

 This occurs in about one and one-half to 

 two and one-half seconds, but the rocket 

 continues to rise, through the force 

 generated, from six to nine seconds. 



In his first camera experiments Mr. 

 Maul used two small rockets com- 

 bined. Here the rotary camera, which 

 could take a picture about one and one- 

 half inches square and had an oblique 

 downward inclination, was in a hood 

 above the rockets. At the sides of the 

 rockets were two chambers containing 

 parachutes of unequal size. The guide- 



staff had two vanes at its lower end, like 

 an arrow, to prevent rotation and change 

 of direction of the lens. At the highest 

 point of the flight a time-fuse raised the 

 shutter and threw out the smaller para- 

 chute. Just before landing, the larger 

 parachute was opened. The double 

 rocket could carry a load of over half a 

 pound and rose about one thousand feet. 

 Failures accompanied successes in the 

 tests. Rockets exploded, parachutes 

 dropped at the wrong moment and much 

 costly apparatus was destroyed, before 

 the inventor saw the cause of his mis- 

 fortunes, which was that the time taken 

 for ascent depend- 



ed on the density 

 and moisture of the 

 air. The exposure 

 and release of the 

 parachutes were, 

 therefore, arranged 

 independently of 

 the period of ascent, 

 by making the up- 

 per part of the hood 

 resilient and equip- 

 ping it with an 

 electric contact de- 

 vice. When the 

 rocket paused for a 

 moment at its high- 

 est point of ascent, 

 the contact opened 

 the shutter and directly afterward threw 

 out the first parachute. This proving 

 successful, the photographic apparatus 

 was enlarged to a diameter of eight and 

 one-half inches; the plates were made 

 four and three-quarters by four and 

 three-quarters inches, the focal distance 

 was also four and three-quarters inches. 

 The length of the equipment was now 

 over thirteen feet and the weight thirteen 

 pounds. As the apparatus was still in- 

 clined to rotate on its axis corrective 

 experiments were made, but the rocket 

 proved unable to carry the weight of 

 a special governing apparatus. Finally, 

 a gyroscopic device was arranged which 

 works automatically when the rocket 



670 



