4i6 History of the Kaleidoscope. 



Upon these principles Dr. B. constructed an instrument, in 

 which he fixed pennimenlly across the ends of reflectors, pieces 

 of coloured glass, and other irregular objects, and he showed the 

 instrument in this state to some menil)ers of the Royal Society 

 of Edinburgh, who were much struck with the beauty of its ef- 

 fects. In this case, however, the forms were nearly permanent, 

 and a slight variation was produced by varying the position of 

 the instrument, witli respect to the light. The great step, how- 

 ever, towards t!»e completion of the instrument remained yet to 

 he made, and it was not till some time afterwards that the idea 

 occurred to Dr. B. of giving motion to oljects, such as pieces oj 

 coloured glass, &c. ivhicli were either fixed or placed loosely in 

 a cell at the end 'f the insirument. When this idea was carried 

 into execution, the kaleidoscope, in its 5i7«p/eyorOT, was com- 

 pleted. 



In this state, however, the kaleidoscope could not be consi- 

 dered as a general philosophical instrument of universal appli- 

 cation ; for it was incapable of producing beautiful forms unless 

 the object was nearly in perfect contact with the end of the re- 

 flectors. 



The next, and by far the most important step of the invention 

 was therefore to remove this limitation by em])loying a draw- 

 tube and lens, by means of which beautiful forms could be created 

 from objects of all sizes, and at all distances from the observer. 

 In this way the power of the kaleidoscope was indefinitely ex- 

 tended, and every object in nature could be introduced into the 

 picture, in the same manner as if these objects had been re- 

 duced in size, and actually placed at the end of the reflectors. 



When the instrument was brought to this state of perfection. 

 Dr. Brewster was urged by his friends to secure the exclusive 

 property of it by a patent, and he accordingly took out a patent 

 for " a New Optical Instrument for creating and exhibiting beau- 

 tiful forms." In the specification of his patent he describes the 

 kaleidoscope in two different forms. The first consists of two 

 reflecting planes, put together according to the principles already 

 described, and placed in a tube, with an eye-liolc in the parti- 

 cular position which gives symmetry and a maximum uniformity 

 of liglit, and with objects, such as coloured glass, placed in the 

 position of symmetry, and put in motion either by a rotatory 

 movement, or by their own gravity, or by loth combined. The 

 second form of the instrument, described in the specification, is, 

 when the tube containing the reflectors is placed in a second 

 tube, at the end of which is a convex lens which introduces into 

 the picture objects of all magnitudes, and at every distance, as 

 has been already described. 



After the patent was signed, and the instruments in a state of 



forwardness. 



