APPENDIX A. 



i. Normal saline solution. 



This solution, or as it is also called normal salt solu- 

 tion or physiological salt solution, is so much used in the 

 physiological laboratory that it should be made in consid- 

 erable quantity and always easily accessible. 



Formula: 



Common salt (C. P.) 30 gms. 



Distilled water 5 L. 



It is convenient to keep the solution in a siphon bottle. 

 It is thus protected from dust and evaporation, and is al- 

 ways easily accessible. See Fig. 53. 



FIG. 53. 

 FIG. 53. Siphon-bottle for normal saline solution. 



2. Frog boards. 



There is probably no more satisfactory or economical 

 frog board than a piece of dressed soft pine 15 cm. by 30 



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