320 PRACTICAL MICROSCOPY. 



THWAITES' FLUID. 



Rectified spirit i oz. 



Creosote (wood) .. .. q. s. 



Distilled water I pint. 



Precipitated chalk q. s. 



Saturate the spirit with creosote, then add the water and a little precipitated 

 chalk. Filter, when the liquid is ready for use. 



RALF'S LIQUID. 



Bay salt I grain. 



Alum i grain. 



Distilled water I oz. 



GLYCERINE AND ACETIC ACID. 



Glycerine 2 oz. 



Glacial acetic acid \ oz. 



GLYCERINE AND GUM. 

 (Farranfs Medium?) 



Gum arabic 4 oz. 



Distilled water 4 oz. 



Glycerine 2 oz. 



Dissolve in the cold. 



DEANE'S MEDIUM. 



Nelson's gelatine I oz. 



Honey 5 oz. 



Creosote 6 drops. 



Alcohol ^ oz. 



Water 5 oz. 



Soak the gelatine in 4 oz. of the water for twelve hours, add the honey, pre- 

 viously heated to nearly boiling point, in a separate vessel, and boil the whole 

 together. When cooled somewhat, add the spirit and water in which the 

 creosote has been dissolved. Afterwards, filter through fine flannel. 



GLYCERINE JELLY (Lawrance's). 



Gelatine I oz. 



Glycerine 6 drachms. 



Camphorated spirit of wine J oz. 



Cover the gelatine with cold water, and allow it to soak until it becomes 

 soft. Dissolve by placing the jar containing it in a vessel of boiling water, 

 and allow it to cool, then add a small quantity of the white of an egg, and boil 

 the mixture until the albumen coagulates, when the whole is to be filtered 

 through fine flannel, and mixed with the glycerine and spirit. 



