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may be so great that, while with one the objective may 

 be condemned as imperfect, it may with the other 

 appear to be of extraordinary excellence. 



In conclusion, I will say that there may be other 

 conditions which may influence the performance of a 

 lens, and to acquire the power of eliminating them 

 requires considerable experience. When an objective 

 does not correspond with the claims of the optician, 

 judgment should not be passed upon it until after 

 repeated trials have been made, in all of which the 

 above points should not be lost sight of. 



