112 



Left-handed Watches for Left 

 Handed People 



A WATCH for left-handed people 

 has been invented by a Kalamazoo 

 jeweler, who believes that the left- 

 handed look at 

 things in a "left- 

 handed" fashion. 

 The left-handed 

 watch runs back- 

 ward. The dial is 

 arranged so that 

 the numeral 1 is 

 on the left hand 

 of 12 instead of 

 on the right as in 

 the case of the 

 ordinary watch. 

 The hands also run from right to left 

 instead of in the usual fashion. Mechan- 

 ically, with the exceptions given, the 

 left-handed watch differs very .slightly 

 from the ordinary time-piece. 



The inventor constructed the unusual 

 watch for the benefit of his daughter, 

 who is left-handed. 



An International Test for Vision 



THE International Ophthalmic Con- 

 gress at_ Naples, in order to intro- 

 duce uniformity in methods of measur- 

 ing vision, has adopted the broken ring 

 of Landolt as the 

 best possible in- 

 ternational test 

 for visual acute- 



O^^ - ^^ ness. But as no 

 f ^ ^ ^ efforts have been 

 *^ ^^ made to use it as 

 cards with test 

 letters are used, it 

 has had little 

 practical value. 

 However, Dr. Edward Jackson, of 

 Denver, has found that if the broken 

 rings are arranged in a symmetrical 

 group and printed, as here illustrated, on 

 a card that can be turned with any edge 

 uppermost, it constitutes a test independ- 

 ent of a knowledge of letters. The test 

 is placed five meters from the patient. 

 If the direction of the break in the rings 

 is recognized at full distance, full acute- 

 ness of vision is demonstrated. If at 

 four and a half meters, the vision is one- 

 tenth defective, and so on. 



COO 



o o o 



Popular Science Monthly 



A Pocket Periscope 



ONE of the 

 interesting 

 inventions which 

 the war in Eu- 

 rope has stimu- 

 lated is a very 

 small, but none 

 the less service- 

 able, pocket peri- 

 scope. The sol- 

 dier, concealed 

 behind an intrenchment, can quickly at- 

 tach this tiny instrument to the barrel 

 of his rifle, to a pole, or to a trench- 

 digging tool, and can readily observe, by 

 means of the two circular mirrors, the 

 movements of his antagonists in the dis- 

 tance without exposing himself to any 

 tance without exposing himself. 



A Trolley for the Stable Lamp 



THE problem 

 of carrying 

 an oil 1 a n t e r n 

 while at work in 

 a barn or garage 

 is an old and per- 

 plexing one, but 

 it has been inge- 

 niously solved by 

 an inventor in 

 South Dakota. 

 Instead of depositing the lantern on the 

 floor, on an upturned box, where its 

 light is usually shed to the least advan- 

 tage, he has devised a simple but effective 

 overhead trolley system. A stout wire is 

 extended across the ceiling between 

 braces, and the lantern suspended on a 

 small wheeled truck from it. 



Non-Rolling Nursing Bottle 



SO many ba- 

 bies these 

 days are bottle- 

 fed that mothers 

 will be interested 

 to know of a new 

 feeding bottle 

 which is flattened 

 at the sides to prevent its rolling over 

 either when baby is feeding or when the 

 mother is washing the bottle. The ounces 

 are scaled upon one side and the rim of 

 the neck is so sloped that the nipple is 

 easily put on. 



