The MicRoscolPE. 53 



Would not be difficult to decide. Tlie stage of the " Investiga' 

 tor" can be rotated, and the mirror may be used above the ob- 

 ject independently of the sub-stage. The former is occasionally 

 a convenience, it is very rarely a necessity, but to have the tail- 

 piece divided into sub-stage arm and mirror-b.'ir is a decided ad- 

 vantage, and would, for me at least, turn the scale of choice in 

 favor of the " Investigator.'^ 



With Messrs Bausch and Lomb's " Universal," and Messrs J. 

 W. Queen and Co.'s "Acme No. 3,^' we may begin to notice some 

 of the refinements and elegancies of the modern microscope* 

 These stands are graceful, beautiful and wliat is better, useful. 

 Both 'possess several commendable devices not ofliered by the 

 preceding forms wliere the chief object is simplicity of design 

 and fewness of parts. In the "Acme No. 3 " the body is nearly 

 of the standard length, the circular black glass stage bears a 

 movable object carrier, and the mirror may be swung above it 

 and the obliquity recorded. Its bar carries a sub-stage, with the 

 Iris diaphragm, for which a condenser may be substituted. The 

 sub-stage has centring adjustments, yet their form cannot be 

 unqualifiedly commended. To the stand almost any piece of 

 apparatus may be added, and with it the student is well armed 

 for most any kind of microscopical work. Nearly the same de- 

 scription may be given of the " Universal " stand, which in some 

 respects, notably in the stage, is simpler. It does not bear the 

 convenient object carrier, but the upper plate rotates. The 

 mirror-bar and the sub-stage arm are separate and graduated, 

 the sub-stage having centring adjustments similar to those of 

 the "Acme No. 3." The body is divided, a tube being necessary 

 to extend it to the standard length, and even this tube carries a 

 draw-tube. Here there is an embarrassment of tubular riches, 

 a feature to which I object. One of my friends has this other- 

 wis-e commendable stand, but one of his bad habits in connec- 

 tion with its use snows the tendency to which this divided body 

 often leads. He is accustomed to incline the instrument, but 

 with both tubes pushed in, thus leaving the body of much less 

 than the standard length ; he then obtains increased magnifying 

 power by using a high power eye-piece. This is the perfection 

 of microscopical laziness ; as I look at him I become momen- 

 tarily lost to all sublunary things except to his consummate indo- 

 lence. In regard to it I have nothing further to say, for I should 



