5> 



64 STRONG DRINK AND TOBACCO SMOKE. 



possess. So that if we found in our cigar a portion 

 of a leaf, either possessing a stalk or a divided margin, 

 we should safely conclude that we had alighted upon 

 an adulteration. 



Moreover, the midiib of tobacco in section presents 

 (as in " bird's-eye" cut tobacco) a horse-shoe form (Plate 



9, fig. 5), in which the ivoody or Jibrous tissue lies as 

 a central mass, surrounded by the cellular tissue. In 

 this latter character it closely resembles foxglove (Plate 



10, fig. 5), but this last differs from it in the ivoody 

 tissue being curved upwards at the ends, and the margin 

 of the section, more particularly on its upper surface, 

 havino' strono; and decided curves. 



In all the leaves with which tobacco is, or is likely to 

 be adulterated, the woody tissues of their midribs, or 

 stalks, lie in separate detached bundles, as will be readily 

 seen on comparing Plate 9, figs. 8 and 11, and Plate 10, 

 figs. 2, 5, and 8, with Plate 9, fig. 5. 



The forms of the leaves of dock (Plate 9, fig. 9), 

 burdock (Plate 9, fig. 6), chicory (Plate 10, fig. 1), fox- 

 glove, and comfrey (Plate 10, fig. 4), with the trans- 

 verse-vertical sections of their midribs, are given in 

 Plates 9 and 10. The peculiar characters of the leaves 

 will be evident on inspection ; those of the sections of 

 the midribs consisting of diSerences in the forms of 

 their outlines, Avhether plain, more or less grooved or 

 lobed, and the general form and distribution of the 

 woody tissues of each amongst the cellular tissue. 



Compare, for instance, the forms of the leaves of 



