'68 Modern Microscopy. 



Lire -cay es. These are not used so largely for water 

 objects as for insects, etc., which may be compressed. They 

 consist of a brass plate having a glass base-plate, over 

 which a cap slides having a very thin cover-glass. The 

 subject to be viewed is placed between these two glasses 

 and held firmly by compression. The best form is that 

 designed by Mr. Rousselet, shown in Fig. 27, with which 

 a condenser may be used conveniently. It is also so 

 arranged that even if a specimen be fixed at the extreme 

 edge of the glass plate, there is room for an objective to 

 work on it. The ordinary live-cages are usually too narrow 

 at the top for this to be done. A very good plan is often 

 adopted by amateurs for viewing live objects as follows: 

 A square flat piece of glass is obtained^ and on this an 

 indiarubber ring is laid, into which the animalculae can 

 be placed ; a thin piece of glass is now put over the top 

 of the indiarubber ring, and this really makes as service- 

 able a trough as can be obtained. 



Forceps. Stage forceps are used to hold unmounted 

 specimens in the field of view while they are examined, 

 there being a fitting on the forceps to go into a hole pro- 

 vided in the limb or the stage of the instrument. 



There are also many modifications of the apparatus de- 

 scribed, and which practical experience will suggest the 

 desirability of using ; but the principal ones, and those 

 most commonly worked with, are mentioned. 



Textbooks recommended : 



Carpenter's * The Microscope and its Revelations,' edited 

 by Dr. Dallinger. 



* The Microscope,' by Dr. Henri van Heurck. 



' Photo-micrography,' by Dr. Bousfield. 



And as periodicals the best are : International Journal of 

 Microscopy and Natural Science, edited by A. Allen, Bath ; 

 and the American Monthly Microscopical Journal, edited by 

 C. W. Smiley, Washington, D.C. 



These journals both contain latest information with 

 respect to the microscope. 



