276 



THE WORLD'S ADVANCE 



even with either of the sidewalks of the 

 street above. 



The concrete work in this instance is 

 reinforced with strong steel rods one- 

 half and three-quarter inch in diameter. 

 At all sides of the steps, where there is 

 no wall cement, column and pipe railings 

 have been provided. The entire concrete 

 work has been given a sanded finish. 



A BATTERY CONTAINER THAT 

 CONNECTS ITSELF 



Every user of dry cells in quantities 

 knows the value of a device which makes 

 it unnecessary to connect each cell when 

 it is put in the place of an exhausted 

 one. . While several practical methods of 

 accomplishing the desired result have 

 been suggested and put into operation, 

 the arrangement shown in 

 the illustration possesses a 

 number of features which 

 may lay claim to the title of 

 being unique. 



nection with the carbon and the other 

 with the bare zinc at the bottom of the 

 cell. Thus it is obvious that by merely 

 removing the paper carton from the cell, 

 or cutting the bottom out of it and press- 

 ing the cell into place, the connection is 

 made and the battery secured in place 

 almost instantly. 



The contacts can be arranged for series 

 or multiple connection or a combination 

 of the two. 



TINY X-RAY PICTURES 



Professor Pierre Goby appears to 

 have been the first man to obtain photo- 

 graphs of very minute specimens by the 

 use of the X-rays, such as diatoms and 

 the like, which have about the size of a 

 grain of sand. This he does by placing 

 the specimens directly upon a photo- 



The contact device in this container 



Two Views of a Battery Container of New 

 Design. Contact with the Battery Terminals 

 is Made Through a Pair of Phosphor Bronze 

 Strips. The Contacts Can Be Arranged 

 for Series or Multiple Connection or a 

 Combination of Both. 



graphic plate and allowing a perfectly 

 vertical beam of the rays to fall from 

 the bulb above, through a special tube 



consists of a pair of phosphor bronze so as to properly direct the rays on to 

 spring strips, one of which makes con- the object. 



