MICROSCOPIC DRAWING AND ENGRAVING. 



however, when he examined the same object %\ith his great fifty- 

 three foot telescope, having six feet aperture, it assumed the 

 appearance shown in fig. 14. 



19. Another very remarkable example of the change of appear- 



Fig. 12. 



ance produced in one of these wonderful objects, is presented in 

 the case of a nebula first observed by Sir Win. Herschel, and 



Fig. 13. 



^described by him as a bright round nebula, surrounded by a halo or 

 glory, and attended by a much smaller companion. Sir John 

 58 



