iiS Hislory of the Kaleidoscope. 



" St. John's, May 19, 18l8. 



*' Sir, — ^The propositions I have given relating to the number 

 of images formed by plane reflectors inclined to each other, con- 

 tain merely the mathematical calculation of their number and 

 arrangement. Tlie effects produced iy the kaleidoscope were 

 never in my contemplation. My attention has for some years 

 been tnrned to other subjects, and I regret that I have not time 

 to read your Optical Treatise, which 1 am sure would give me 

 great pleasure. I am, sir, 



*' Your obedient humble servant, 



" J. Wood." 



The next supposed anticipation of the kaleidoscope was an 

 instrument proposed by Mr. Bradley in 1717. This instrument 

 consists of two large pieces of silvered looking-glass, Jivt 

 inches wide aitdjour inches high^ jointed together with hinges, 

 and opening like a book. These plates being set upon a geo- 

 metrical drawing, and the eye being placed in front of the mir- 

 rors, the lines of the drawing were seen multiplied by repeated 

 reflections. This instrument was described long before by Kir- 

 cher, and did not receive a single improvement from the hands 

 of Bradley. It has been often made by the opticians, and was 

 principally used for multiplying the human face, when placed 

 between the mirrors ; but no person ever thought of applying it 

 to any purpose of utility, or of using it as an instrument of ra- 

 tional amusement, by the creation of beautiful forms. From 

 the very construction of the instrument, indeed, it is quite in- 

 capable of producing any of the singular effects exhibited by the 

 kaleidoscope. It gives, indeed, a series of reflected images ar- 

 ranged round a centre ; but so does a pair of looking-glasses 

 placed angularly in an apartment, and so do the pieces of mirror 

 glass with which jewellers multiply the wares exhibited at their 

 windows. It might therefore be as gravely maintained that any 

 of these combinations of mirrors was a kaleidoscope, as that 

 Bradley's pair of plates was an anticipation of that instrument. 

 As the similarity between the two has been maintained by igno- 

 rant and interested individuals, we shall be at some pains to ex- 

 plain to the reader the differences between these two instru- 

 ments ; and we shall do this, first, upon the supposition that the 

 two instruments are applied to geometric lines upon paper. 



1. In Bradley's instrument, I. In the kaleidoscope, the 

 the length is less than the length of the plates must be 

 breadth of the plates. four, or five, or six times their 



breadth. 



2. Bradley'^ iivstrumeut can- 2. The kaleidoscope cannot 

 not be used with a tube. be used without a tube. 



3. Ill 



