136 



APPENDAGES TO THE MICROSCOPE. 



its contents remain in it when the tube is lifted out, and may 

 be deposited on a slip of glass or on the lower disk of the 

 Aquatic Box, or, if too copious for either receptacle, may be dis- 

 charged into a large glass cell (Fig. 106). In thus fishing for any 

 but the minutest objects, it will be generally found convenient to 

 employ the open-mouthed tube c ; and when its contents have been 

 discharged, if they include but a single object of the desired 

 kind, this may be taken up by one of the finer tubes, A, B, or, if 

 more convenient, the whole superfluous fluid may be sucked up by 

 the mouth, and the object left with no more than is suitable ; or, 

 if there be many of the objects in the fluid first selected, these 

 may be taken up from it, one by one, by either of the finer tubes. 



101. Glass Syringe. — In dealing with minute Aquatic objects, 

 great advantage will be found in the use of a small Glass 

 Syringe of the pattern represented in Fig. 83, and of about double 

 the dimensions. "When this is firmly held between the fore and 



Fig. 83. 



m\ 



1 



Glass Syringe. 



middle fingers, and the thumb is inserted into the ring at the 

 summit of the piston-rod, such complete command is gained over the 

 piston that its motion may be regulated with the greatest nicety ; 

 and thus minute quantities of fluid may be removed or added, or 

 any minute object may be selected (by the aid of the simple Micro- 

 scope, if necessary) from amongst a number in the same drop, and 

 transferred to a separate slip. A set of such Syringes, with points 

 drawn to different degrees of fineness, and bent to different curva- 

 tures, will be found to be among the most useful ' tools ' that the 

 working Microscopist can have at his command, as they are 

 capable of a great number of applications, several of which will 

 be particularized hereafter. 



102. Forceps.— Another instrument so indispensable to the 

 Microscopist as to be commonly considered an appendage to the 



Fig. 84. 



Forceps. 



Microscope, is the Forceps for taking up minute objects; many 

 forms of this have been devised, of which one of the most con- 



