LOOKING THROUGH THE HAND. 



Shortly, the left eye sees part of the wall, 

 and the right eye sees part of the palm. The 

 brain combines them as one image a round 

 piece of wall seen through a round hole in 

 the hand the rest of the images being 

 neglected. 



That these things are only neglected, not 

 unseen, can easily be shewn by helping some 

 of them to attract attention in a way very 

 similar to that once adopted by ladies in the 

 beauty patch. Let a small piece of stamp- 

 paper be stuck in the palm just where the 

 hole is to appear. This will come into view, 

 and by careful observation it will be possible, 

 while still focussing the wall, to see the part 

 of the palm where the hole is, and even to 

 detect some of the palmistry lines in this 

 area. 



Similarly, if a tiny hole be made in the 

 side of the tube, this will let light through, and 

 so make it possible to attend to the image 

 of the inside of the roll, on which writing, 

 printing, or parallel lines may be observed. 



4. Blue and Yellow not producing Green. 



Those who in their childhood played with a 

 box of colours' and how many have not done 

 so ? soon learned that when the green tablet 

 was lost, a fair substitute could be got by 

 mixing blue and yellow, just as a mixture of 



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