MICROSCOPICAL EXAMINATION OF FLOUR. 
Table 2. — Variation in counting of each analyst. 
Slide. 
Count 
No. 
Bran particles. 
Hairs. 
Jan. 7, 
1918. 
Jan. 8, 
1918. 
Jan. 9, 
1918. 
Jan. 7, 
1918. 
Jan. 8, 
1918. 
Jan. 9, 
1918. 
A 
Keenan. 
1 
2 
2 
1 
2 
Lyons. 
1 
2 
1 
2 
1 
2 
87 
92 
60 
60 
87 
81 
103 
114 
86 
80 
90 
87 
76 
82 
60 
49 
62 
64 
100 
96 
85 
77 
89 
83 
80 
83 
49 
53 
60 
77 
104 
106 
78 
77 
86 
86 
59 
64 
60 
58 
62 
74 
58 
52 
64 
58 
62 
59 
66 
69 
55 
48 
66 
68 
54 
56 
52 
55 
65 
62 
65 
A .. 
66 
B 
61 
B... . 
57 
C 
66 
C 
71 
A 
54 
A 
55 
B 
55 
B " 
55 
C... 
66 
c 
63 
COUNTING THE SAME SLIDE ON THE SAME DAY BY TWO ANALYSTS. 
The variation between the counts made by two analysts on the 
same slide on the same day is demonstrated by comparing the daily 
averages * obtained by each of the two analysts. These data are 
compiled in Table 3. 
Table 3. — Variation in counting of two analysts on same day. 
Date. 
Analyst. 
Bran particles. 
Hairs. 
Slide A. 
Slide B. 
Slide C. 
Slide A. 
Slide B. 
Slide C. 
1918. 
89 
108 
19 
79 
98 
19 
81 
105 
24 
60 
83 
23 
54 
81 
27 
51 
77 
26 
84 
88 
4 
63 
86 
23 
68 
86 
18 
61 
55 
6 
67 
55 
12 
65 
54 
11 
59 
61 
2 
51 
53 
2 
59 
55 
4 
61 
Jan. 7 
59 
9 
(Keenan 
67 
Jan. 8 
■| Lyons 
62 
[Variation 
5 
(Keenan 
63 
Jan. 9 
63 
5 
The table shows an average variation in the count of bran par- 
ticles of 20, with a range of from 4 to 27. The average variation in 
the count of hairs was 18, with a range of from 2 to 12. It is evident 
that the variation between analysts in making the count of bran 
particles is greater than in making the count on hairs. 
DAILY VARIATION DUE TO CONDITION OF LIGHT, ETC. 
To determine what influence, if any, physical conditions, such as 
degree of light, have upon the count, it is necessary to first eliminate, 
as far as possible, the personal variations already considered. This 
may be accomplished by taking the average of two counts on three 
1 By "daily average" is meant the average of two counts made by the same analyst on the same slide 
on a given day. 
