REPORT OF THE CHEMIST. 



91 



PARTS OF THE "WHEAT GRAIN IN DIFFERENT MILL PRODUCTS. 



2001. Wheat at it enters the mill. — The whole wheat grain mixed with cockle, oats, and 



other foreign seed, as it comes from the thrasher. 



2002. Wheat prepared for the rolls.— The foreign seeds have been removed, with the ex- 



ception of a lew grains of cockle aud oats. The cockle is therefore to be 

 found in subsequent partst>f the process. The hairs have been largely rubbed 

 oil", together with portions of the cuticle. Some hairs are, however, still left, 

 aud portions of the cuticle remain attached and semi-detached, especially to- 

 ward the crease. The grain as a whole presents a changed and much, cleaner 

 appearance. 



2003. Co'kleami screenings. — Among the foreign seeds there are found principally 



cockle and a species of polygonum and oats, together with broken pieces of 

 wheat, dirt, chatf, &c. 



2004. Scour'uujs removed by cleaners. — These consist almost entirely of cuticle and hairs, 



but portions of epical^), with the hairs still adherent, and of endocarp are 

 present. Treatment with iodine reveals a small amount of endosperm or 

 starch, aud shows the inner part of the outer coats of the grain are the most 

 highly nilrogenous. The contrast between the embryous membrane and en- 

 docarp and the epicarp and cuticle is prominent. The embryous membrane 

 is recognized by its roundish cells ; the endocarp by its transverse cells, twice 

 as long as broad, and packed closely and regularly, like cigars, which has 

 given it the name of cigar-coat, and the epicarp by its very long and irregu- 

 lar cells arranged longitudinally, the cuticle being of a similar sort. 



2005. First break. — The grain is split along the crease normally into two halves, but 



also frequently into fours, or even more irregularly. The glistening, hard, 

 lloury endosperm makes its appearance for the first time. Comparatively 

 little flour or dust is made. 



2006. Chop from first break. — This consists principally of endosperm, but small portions 



of bran * and germ are present, the former including all the various outer 

 coats. 



2007. Second break. — In this break the greater part of the endosperm is separated from 



the bran, and is seen as large vell-shapen middlings, together, of course, with 

 some small stuff and dust. 



2008. Chop from second break.— This is chiefly endosperm, with somewhat less bran 



than the previous chop. Whole germs and parts are numerous. The endo- 

 sperm is of all sizes, but the greater portion of large angular fragments. The 

 bran includes portions of all the outer coverings, while dusty matter and 

 starch grains are quite abundant. 



2009. Third break. — The endosperm is so completely separated in this break that it 



only remains in scattered patches upon the bran, and the embryous membrane 

 is quite visible. 



2010. Chop from third break. — The middling or particles of endosperm are much finer, 



and there is more dust. Small portions of germ are plentiful. The branny 

 particles are similar in nature to those in the last chop but smaller, and there 

 is more dust of a nitrogenous kind. 



2011. Fourth break. — Only to be distinguished from No» 2009 by the slightly cleaner 



bran. 



2112. Chop from fourth break. — Not very different in appearance from 2010, except that 

 it is composed of more finely divided particles. 



2013. Fifth break.— Still cleaner bran than 2011. It still holds a very appreciable por- 



tion of endosperm. 



2014. Chop from fifth break.— Chop contains a great deal of branny matter, including 



pieces of epicarp, endocarp, aud embryous membrane. The endosperm is very 

 fine and much mixed with germ. Of course in all these products portions of 

 the testa and tegmen are present, but they are not easily seen except in 

 careful preparations. 



2015. Sixth break. — Barely distinguishable from bran. 



201(3. Chop from sixth break. — Very largely made up of small pieces of branny material 

 and germs. The endosperm which is present is very fine. 



2017. Lrnn. — This is composed practically of epicarp, endocarp, and embryous mem- 



brane, the cells of the latter having been very little disturbed. There is still 

 a little cuticle and endosperm left, but they have mostly disappeared in pre- 

 vious operations. 



2018. Sh oris— These are made up of all the different parts of the grain in rather a 



fine condition, some of the branny particles having endosperm still adherent 

 to them. 



* Bran is used in this description as denoting and including any part of the coats 

 of the grain. 



