A STUDY OF WHEAT. 



59 



and simple grains. The compound grains or masses are either 

 cylindrical or prismatic. When cylindrical the curving surface is 

 perfectly smooth, but the ends are irregular as though they had 

 been broken. These masses are very numerous and characteristic, 

 unfortunately they closely resemble the cell contents of black 

 pepper. These compound grains are much larger than those of 

 oat. They are quite opaque and show distinctly the divisions into 

 small, single grains ; many of the small grains are like the cor- 

 responding ones of oat in having two or more plain sides and 

 the remainder of the grain curved. They are larger than 

 oat, being one three-thousandth to one sixteen-hundredth of an 

 inch in diameter They are quite irregular in size, and generally 

 a nucleus is present. There are no rings. 



g. 4. Buckwheat Starch. X 475. {Drawn with the camera lucida.) 



If you suspect the sample of flour which you are examining 

 contains either oat or buckwheat, ii. will be much easier to examine 

 it first with a low magnifying power (something less than 150 

 diameters) and decide the question of the compound grains or 

 masses first, then examine it with a higher power. Fortunately 

 for humanity the best qualities of flour are almost invariably 

 what they profess to be, "pure wheat flour." The mixtures and 

 adulterations of other flours and too often mineral substances 

 are found in the cheapest, poorest flour in market. 



