184 THE presidekt's address. 



" turn-out " substages, intended to carry a chromatic or other 

 condenser, paraboloid, spot lens, polariscope, and a host of other 

 apparatus such as would be suitable only for a full-sized, complete 

 stand of the English model. I confess that when I see small 

 stands of this class encumbered with milled heads and other 

 projections, both above and below the stage, and overweighted 

 with complicated and costly accessories, I am at a loss to 

 understand how they can be used to any good effect by the 

 average student. It cannot, therefore, be too strongly asserted 

 that instruments of the kind I have now been considering are, 

 in their nature, working or mounting instruments only, and that 

 any attempt to raise them to a higher position, by the addition 

 of elaborate mechanical appliances, can only result in failure 

 and disappointment. 



But there is another type of instrument, seldom met with 

 now, but which in my early days used to be called the Student's 

 microscope, and, in my opinion, much more appropriately. The 

 stands I refer to were of full English size, and of first-class 

 material* and workmanship. They were supplied by their 

 makers in a plain, elementary form ; being fitted, in the first 

 instance, with nothing more than coarse and fine movements 

 to the body, simple square stage and sliding bar; but they 

 possessed the very obvious advantage that they were capable of 

 being built up into instruments of great completeness, according 

 to the wish or means of the purchaser, and having been originally 

 designed accordingly, they were not overbalanced by subsequent 

 additions. Thus a mechanical stage, with universal movements, a 

 rack-and- pinion focussing substage, with centering and rotating 

 adjustments, could be adapted, binocular bodies could be added 

 if desired, and all other apparatus required by the most accom- 

 plished microscopist. I believe that I am not awarding praise 

 unfairly when I say that the firm of Boss & Co. were the first 

 to introduce this excellent plan, which was subsequently adopted 

 for a brief season by most of the other London opticians. I 

 purposely bring into prominence what is now — unfortvmately, as I 

 think — a matter of ancient history, because I am confident that 



* I am afraid that the brass of which many of our stands are made 

 nowadays is sadly inferior to that which used to be employed for that 

 purpose ; much of it is so soft that, as a brass-worker once phrased it, 

 ,' You can almost bite it through with your teeth." 



