SOMETHING ABOUT AMERICAN STANDS, ETC. 33 



on the absolute importance of looking carefully to the 

 entire apparatus connected with the hanging of the 

 mirrors. This part of the mechanism is called to 

 endure more fatigue, and is oltener thus called on than 

 any other portion of the stand. For instance : In the 

 act ot observing, one often has occasion to seize the 

 mirror, and to move it and the radial arm by a single 

 impulse, simultaneously as it were ; and here let me say 

 that it will be well for the observer to acquire this 

 habit; nevertheless, it is terribly straining on the 

 joints thus called on, and they should be strong enough 

 to endure the fatigue. 



See also that all the eye pieces slip in and out of the 

 tube easily; this too without decentring the object in 

 the field. Any difficulty in putting eye pieces in place 

 or removing therefrom is a first class botheration. 



o 



We now proceed to the description of the stands 

 made and sold by American makers. In placing Mr. 

 Joseph Zentmayer at the head of this list, the author 

 feels assured that he does no violence to the feelings of 

 others. Mr. Zentmayer was one of our earliest and most 

 energetic makers, and his work has, as a rule, proved 

 honest and reliable. In his expenditure of capital, his 

 facilities for execution, or his pride in presenting first- 

 class work, he stands second to none, as his competitors 

 will generally attest. 



Mr. Zentmayer's largest and most costly stand has, I 

 may say, but just been placed on the market. It was 

 especially designed for exhibition at the Centennial 

 Exposition. The description which follows is to a con- 



