SOMETHING ABOUT AMERICAN STANDS, ETC. 31 



Second. The binocular instrument is much more 

 complicated, and hence more expensive, the purchaser 

 ~being required to pay, without getting in return value 

 received. 



Third. This form does not admit of the instrument 

 being used with short, as well as standard tube, and to 

 the " worker " this item has particular force. 



Fourth. The extra expense attending the purchase 

 of a binocular can be better applied in other directions. 

 Those who value dollars and cents will find force in 

 'this objection. 



Fifth. I oppose the binocular, because the monocu- 

 lar is good enough, and because the real work of the 

 microscope has been and will continue to be done with 

 the monocular. 



Sixth. The binocular is to a certain extent impract- 

 icable, because the two eyes of the observer are not 

 alike. There are exceptions, but not to an extent suffi- 

 cient to invalidate the rule. 



Seventh. I oppose the usual form of binocular 

 instruments, believing that the binocular eyepiece 

 invented and made by Mr. K. B. Tolles is a preferable 

 way of obtaining binocular vision. 



Having thus presented my objections, let the reader 

 elect for himself, with this assurance on my part, viz., 

 better get a good binocular than a poor monocular. 



All stands should be furnished with plane and con- 

 cave mirrors. If the mirrors are attached to radial arm, 

 hinged at a greater or less distance from the under sur- 

 face of the stage, then it is apparent that when the 



