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its colour is in tlie first instance very dark and dirty looking, and soon 

 becomes quite black. 



Next in importance to mustard, Pepper is most largely used. It also 

 is mixed with flour and other organic matters, but we have failed to 

 find any mineral ingredient. Here also the microscope furnishes the 

 readiest means of discovering admixtures, as the histogenic charactei's 

 of the pepper corn ai-e very distinct. There are two kinds of pepper in 

 commerce, the Black and the White. The former consists of the semi- 

 ripe berry, plucked from the tree and dried entire. This possesses the 

 peculiar pungency and acridity for which pepper is so highly prized, 

 in a much greater degree than the white pepper, which consists of the 

 fully ripe berry, denuded, by maceration, of its epidermal coat. This 

 coat, constituting the husk, is composed of several membranes. The 

 outeraiost consists of large, thick walled, deeply pitted cells, filled with 

 a dark brown colouring matter, and united to form a continuous mem- 

 brane, by a lacework of small cubical cells, firmly adherent to one 

 another. Immediately beneath this is a delicate membrane, consisting 

 of distinct thin walled cells, of a somewhat rounded or elongated form, 

 and filled with a greenish colouring matter ; the remainder of the husk 

 consists of several rows of large, loose, irregularly formed cells, filled 

 with innumerable yelloio oil globules. None of these forms of tissue 

 should be found in white pepper, but separating the husk from the body 

 of the seed, bundles of vascular fibre, consisting chiefly of spiral vessels, 

 are found; these are in part removed with the husk, but in part remain. 

 The external layer of cellular tissue, forming the body of the seed, 

 consists of longish, thick walled cells, loosely attached to each other, 

 and filled with a brownish grey granular matter ; these are interspersed 

 by groups of cells of a somewhat similar shape and size, but more 

 adherent, and filled with a dark orange yellow substance. The body of 

 the seed is composed of large cells, slightly adhering to one another. 

 The more external cells are emptied and more or less collapsed, and 

 their walls very much pitted and broken up, the interspaces being filled 

 with oil globules ; but as they approach the centre of the seed the cells 

 become filled and more rounded in form, and many of them assume a 

 yellow colour after long soaking in water — these are the cells which contain 

 piperine, the peculiar acrid principle of pepper. The others are filled 

 chiefly with small angular starch grains and delicate acicular raphides. 

 All these forms should be present iu ground black pepper, but in ground 

 white, only such as we have described as composing the body of the 

 seed. In those samples of pepper we have examined, we found large 

 quantities of starch. One sample we examined some time since contained 

 very large quantities of wheat and sago flour, having a very white 



