to 
ml. Standard Nitrate Solution to 10.00 ml. with distilled 
water. (1.00 ml. of Standard Nitrate Solution = 1.00 
mg. N.) 
PREPARATION OF SAMPLES 
A. 
D. 
Grind to a fine granular form a small amount of sus- 
pected coprolitic material. 
Add 10 ml. distilled water and shake thoroughly. 
Pass this mixture through a glass filter, separating out 
all loose particles. 
Collect the filtrate; this is the prepared sample. 
PREPARATION OF REAGENTS 
A. 
B. 
Sodium Chloride Solution: dissolve 300 g. sodium 
chloride and dilute to 1,000 ml. with distilled water. 
Sulfuric Acid Solution: add 500 ml. concentrated sulfur- 
ic acid to 125 ml. distilled water. Cool to room tempera- 
ture before using. 
. Brucine-Sulfanilic Acid Solution: dissolve | g. brucine 
sulfate and 0.1 g. sulfanilic acid in 70 ml. hot distilled 
water. Add 3 ml. concentrated hydrochloric acid, cool, 
and make up to 100 ml. with distilled water. 
PREPARATION OF BLANK 
A. Prepare reagent blank by measuring out 10 ml. distilled 
water. 
B. Run test procedure as in 5, including water baths and 
addition of reagents. 
TEsT! 
A. Place all standards, samples and blanks to be tested in 
test tubes in a cool water bath and add 2 ml. sodium 
chloride solution. 
'This test eliminates interferences of nitrites ( NO>) and chlorides. Interferences due to 
excess organic material are removed by filtration through glass (See 2-C.). 
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