CHAPTER YII. 



TOBACCO AND SOME OTHER LEAVES. 



If the reader has mastered the detail of the foregoing 

 chapters, he will find what follows of some use, should 

 he care to analyse for himself the tobacco which he 

 smokes or chews, or the snuif which he uses. 



Most of the tobacco leaves imported into this country 

 arrive packed in large hogsheads, in which after packing 

 they are submitted to an enormous pressure. They 

 rarely suff*er any injury in this process, and for purjDOses 

 of microscopic analysis are, after steeping in water, 

 nearly as useful as if green and freshly plucked. Com- 

 paring the margins of any tobacco leaves with those of 

 other plants we shall find them entire, that is, even 

 and unbroken (Plate 9, fig. 1), unlike the borders of 

 other leaves cut into toothed notches, or into rounded 

 segments, or into larger segments like the dandelion leaf. 

 American, German, Dutch, and most of the tobacco 

 leaves of cormnerce are without stalks, being attached 

 to the stem of the plant by the midrib, or large central 

 vein ; and this is a very marked character which they 



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