8 
BULLETIX 168^ U. S. DEPAETMEXT OF AGKICULTUEE. 
Heat-damaged and maliogany Tcernels. — Corn wliich has become dis- 
colored as a result of heating due to fermentation or fu^e damage shall 
be classed as ''heat damaged." Badly discolored and darkened 
kernels shall be classed as ''mahogany" corn. Xo heat-damaged 
kernels are sho^^^l in the colored plate. 
DETERMINATION OF DAMAGED CORN. 
The percentage of damage should be made on the screened sample, 
preferably by using the entire quantity that remains after removing 
the foreign material and "cracked" corn. In order to simphfy the 
determination for damaged corn and to avoid a double penalty, the 
damaged "cracked" corn, as used in these grades, shall be considered 
simply as "cracked" corn; that is, the small quantity of damaged 
"cracked" corn should not be picked out after screening and classified 
as a part of the damaged corn. An excess of damage in tha " cracked " 
corn will be evidence of a will- 
ful adulteration and a viola- 
tion of general rule No. 10 of 
the grades. 
FOREIGN MATERIAL. 
The foreign material, in- 
cluding dirt, . pieces of cob, 
other grains, finely broken 
corn, etc., as provided for in 
column 4 of Table I, should 
include not only material that 
will pass through the sieve 
with holes nine sixty-fourths 
of an inch in diameter, as shown in figure 6, but should also in- 
clude the coarser foreign material, such as is shown in figure 7. 
It Tsill be found after a little experience that the coarse material 
sho^\ii in fig-ure 7 can be taken out very quickl}" by hand picking 
after the finer material haa been removed by screening, whenever such 
hand picking is necessaiy to determine correctly the grade of the 
grain in question. 
CRACKED CORN. 
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fiG. 5. — Immature skeleton kernels which would be 
removed by fanning or blowing and should therefore 
be classified as foreign material. (Natural size.) 
As provided for in general rule No. 9, all coarsely broken pieces of 
kernels that will 2:>ass through the metal sieve perforated with round 
holes one-quarter of an inch in diamet-er (first sieve) and are re- 
tained on the sieve with the smaller perforations (second sieve) 
shall be considered as "cracked" corn, as shown in figure 8. More- 
