DECEMBER 235 



XO 



A new joy has been added to field studies, so per- 

 fect as to exceed the most extravagant expectations. 

 Everybody must have found the ordinary Assisted 

 binocular unsatisfactory; both eye-pieces Vision 

 have to be adjusted to the same focus, and few people 

 have eyes of even approximately equal power. Most 

 sportsmen, therefore, adhere to the single spy-glass, 

 which is excellent, no doubt, but fatiguing to the eye. 

 Herr Zeiss, of Jena, has come to the rescue by inventing 

 a binocular, of which each tube is adjusted separately 

 to focus. More much more than that the instru- 

 ment is constructed on the reflecting principle of an 

 astronomical glass, which gives great magnifying power 

 within a very little compass, and, at the same time, 

 extraordinary clearness of vision over an extended 

 field. For deer-stalkers this invention is simply 

 priceless, providing them with what is practically a 

 pair of long-distance spectacles of high power, so light, 

 that they may be fixed by a fastening round the head, 

 leaving the hands free. Needless to say what a boon 

 they will prove to the field naturalist. 



As a source of amusement, and more than amuse- 

 ment, it is strange how seldom one sees the spy-glass 

 made use of by people out for pleasure in the country. 

 The flight of birds, the course of streams, mountains, 

 rocks, ruined towers, passing ships all contribute, 

 often insensibly, to their enjoyment; yet it hardly ever 

 occurs to anybody how indefinitely this enjoyment may 

 be increased by very simple means. Even a small case 



