112 



ELEMENTARY CHEMICAL MICROSCOPY 



means of shellac or balsam. The short pieces of tube fit snugly 

 into the hole in the cork and are pressed tightly against the object 

 slide. The tubes are thus easily removable and readily cleaned. 



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 Scale Divisions 



FIG. 56. Calibration Curve of a Seibert Microspectroscope. 



The position of maximum intensity of an absorption band 

 should always be determined by observing the situation of the 

 vanishing point of the band after repeated dilutions. 



It should be borne in mind that the position of a band may 

 be changed greatly through increased or diminished dissociation, 

 and that the absorption bands given by a crystal may be quite 



