Popular Science Monthly 



849 



T' 



A Device Invented by a Blind Doctor to 

 Enable Himself to Write Letters 

 MIE grcitcst sufferers of the present 

 war are the soldiers wlio have been 

 blinded. To palliate their miser\- 

 French soldiers who ha\e lost 

 their sight are urged to use the 

 suggestions of a book called "A 

 Blind Man to the Blind," writ- 

 ten some time ago by a scien- 

 tist, Dr. Emile Javal, who 

 when he found his sight going, 

 tried to prepare himself for 

 his days of blackness. Dr. 

 Javal managed lo write the 

 book with his own hand. 

 The de\'ice he invented is 

 shown in the accompanying 

 illustration. The difficulty 

 in writing without seeing is 

 that although the first line 

 may be fairly straight the 

 following lines are apt to 

 o\'erIap. Dr. Javal's inven- 

 tion consists of a tablet set 

 on a slide resting on a 

 toothed board. The catch 

 of the slide is pressed by a 

 spring into one of the openings between the 

 teeth of the board, thus forming a kind of 

 rack-bar. The end of the board has a rest 

 for the elbow, which rest keeps the pen at a 

 (i.xed distance from the end of the slide. 

 By means of the catch and spring the tablet 

 is moved at the end of 



each line and set in place 



for the next line. The 



paper is held on the tablet 



by a clip; the end of a 



line can be revealed by the 



sense of touch. 



Dr. Ja\al made con- 

 stant use of his tablet un- 

 til his death. Men of 



little education can hardly 



gain as much benefit from 



such inventions, Init as 



the blind should be en- 

 couraged in the use of 



whatcNcr preserves their 



individuality, soldiers who 



have lost their sight will 



be taught the use of some 



such method of expressing 



their thoughts. A plain, 



unvarnished recital of any 



one man's experiences in 



the war would be of 



real literarv ^"alue. 



w 



Dr. Javal's 

 device is 

 simply a 

 tablet set 

 on a slide 

 resting on a 

 toothed 

 board 



Why We Remember Those 

 Big Snow- Storms of Youth 

 'H\ do most pef)ple 

 believe that the win- 

 ters were more se\ere and 

 were attended in- heavier 

 snowfall in their child- 

 hood days than they are 

 now? The myth of the 

 "old-fashioned winter" is 

 almost uni\ersal, and is 

 another exam[)le of "count- 

 ing the hits and not the miss- 

 es." Heavy snow and in- 

 tense cold produce a more 

 lasting impression upon the 

 mind than open, mild weather. 

 \\'e remember the exceptional 

 weather of the past, and forget 

 the normal weather. In some 

 cases a change of residence ac- 

 counts for this belief. Some 

 parts of the country ha^■e a 

 much heavier snowfall than 

 others. In any given locality 

 the weather conditions are 

 usually uniform. 



The medicine vials are placed in 

 separate compartments in the belt 

 as if they were so many cartridges 



A Medicinal Cartridge-Beit for 

 Peaceful Expeditions 



THE man who is hunting for health 

 instead of for wild animals can wear a 

 medicinal cartridge-belt recenth- devised by 

 Dr. Otto Sommer, of Seat- 

 tle, Washington. The belt 

 ismade of canvas or leath- 

 er, as desired, and it has 

 numerous compartments 

 tor vials containing medi- 

 cine, just as a cartridge- 

 Ik-1 t has holes for cartridges. 

 When a person wearing the 

 belt wishesto takeashotat 

 some internal di.sorder he 

 plucks a medicinal pellet 

 from the belt and swal- 

 lows it. If relief does not 

 follow he jilucks another 

 of a diflerent kind imtil 

 his medicinal ammunition 

 is depleted. 



At this point he dons 

 another belt fulh- loaded 

 and repeats the operation. 

 The inxentor claims the 

 belt is useful on long 

 walks, trips, and on 

 horseback expeditions. 



