124 PRACTICAL HISTOLOGY. 



pipette, place a particle of the deposit in such a cell, add a 

 drop of the preservative fluid, and seal up. 



217. Urates. Mount in weak spirit or glycerine solu- 

 tion (see 221). 



2 1 8. Cystine. Mount in dilute acetic acid (ordinary, 

 pyroligneous acid i part, water 20 parts). 



219. Triple Phosphate. Mount in strong ammonia 

 i part, water 6 parts. 



220. Calcic Phosphate is usually amorphous, but 

 sometimes occurs in rosettes of crystals. These may be 

 readily obtained by simply adding to urine a small piece of 

 calcium chloride. The precipitate is allowed to form in a 

 conical glass, and may be mounted and preserved in the 

 mother liquor. 



221. Uric Acid and Oxalate of Lime. Mount in 

 equal parts of glycerine and camphor water. (Camphor water 

 is thus prepared : wrap 3 grammes of camphor in a piece of 

 muslin, place it in a bottle containing 150000 of water, 

 shake repeatedly. The fluid is ready for use in three or 

 four days). Or they may be mounted in glycerine jelly as 

 follows. Wash the deposit in weak spirit. Heat the 

 glycerine jelly in a water bath until it becomes fluid. Place 

 a drop on a warm slide, add the urinary deposit, and after 

 a few seconds apply a warm cover-glass. When the jelly is 

 cold, scrape it away from the edge of the slide, and seal 

 up with zinc cement, to prevent the hygroscopic jelly from 

 attracting moisture from the air. As the jelly answers 

 admirably, the use of Canada balsam or dammar is un- 

 necessary ; and this is fortunate, for the use of these 

 media in this connection is attended with considerable 

 difficulty. 



222. Casts and Epithelium. Pus and mucus may be 

 preserved in naphtha and creosote fluid prepared as fol- 

 lows : (Beale) A, creosote, 35CC; B, wood naphtha, 

 28CC; C, precipitated chalk, 130 grammes; D, water, 

 6ooCC. Mix thoroughly A and B and C in a mortar; 

 very gradually add D, keeping the mixture in motion with 

 the pestle all the while. Place the whole, together with a 

 few pieces of camphor, in a lightly covered vessel for two 



