1 82 MICRO-CHEMISTRY. \CH. VII. 



air some distance above an alcohol or Bunsen flame ; mount in xylene balsam 

 {\ 300)1 or one may fuse the salt with the balsam (§ 300) ; 5. Copper acetate; 

 Mount dry ($ 231) ; 6. Copper sulphate. Crystals much more satisfactory when 

 examined in the "mother liquor." 7. Lead nitrate; 8. Mercuric chlorid (corro- 

 sive sublimate), mount in xylene balsam (\ 300, 240). 9. Nickel nitrate, obtain 

 crystals by heating; mount in xylene balsam (§ 240, 300) ; 10. Potash alum; n. 

 Potassium chlorate; 12. Potassium dichromate. Compare specimen crystallized 

 by heat and spontaneously; mount dry or in xylene balsam (§ 300). 13. Po- 

 tassium iodide. Dilute with one or two volumes of water, and crystallize by heat. 

 14. Potassium nitrate; 15. Potassium oxalate; 16. Potassium sulphate; 17. Sali- 

 cin. Fuse the dry salicin on the cover-glass, mount dry, or preferabl)' fuse in 

 balsam (§ 300). 18. Salicylic acid. Make a 10% solution in 95% alcohol ; let it 

 crystallize spontaneously in the air; mount dry ($ 231). 19. Sodium chlorid 

 (common salt). Mix sat. aq. sol. with one or two volumes of water, and heat ; 

 mount dry or in balsam. 20. Sulphonal (§ 21S). 



\ 322. For directions and hints in micro-chemical work and crystallography, 

 consult the various volumes of the Journal of the Roy. Micr. Soc. ; Zeitschrift fur 

 physiologische Chemie, and other chemical journals ; Wormly ; Element & Re- 

 nard ; Carpenter-Dallinger ; Hogg ; Behrens, Kossel mid Schiefferdecker ; Frey ; 

 Dana, and other works on mineralogy ; Davis. 



