484 APPENDIX. 



Three or four small thin glass beakers. 



Half a dozen watch-glasses. 



Three or four glass salve-pots with lids. 



B. ON DISSECTING. 



Unless otherwise directed, all the dissections embraced by 

 this work should be performed under water. 



The undermentioned precautions are indispensable to success. 



1. The animal or organ under dissection should be firmly 

 pinned down, the pins being thrust through those more 

 solid parts of the same, furthest removed from the point 

 of operation. 



2. Displacement of parts of organs, prior to removal or 

 otherwise, should be effected by means of forceps, the 

 larger ones being employed wherever possible (in order 

 that the smaller ones may be the more fit for delicate 

 work) ; the direct use of the fingers should be dis- 

 couraged. 



3. Never dissect under dirty water. Should the water be- 

 come clouded, as it may do from numerous causes, 

 change it at once and, in doing so, wash the dissection 

 clean under a gentle stream. 



4. In dissecting a given system remove nothing unneces- 

 sarily. Dissect away only such parts as may interfere 

 with the immediate purpose of inquiry, and do this only 

 after full deliberation. 



5. Dissecting instruments should always be wiped perfectly 

 clean and dry after use. The hinges should be occa- 

 sionally oiled by means of a camel's hair-brush ; and if 

 put away for a lengthy period after use, all parts subject 

 to immersion in water should be similarly treated. 



