32 
BULLETIN 1375, U. S. DEPARTMENT OF AGRICULTURE 
priming test before a regular test, after the machine has stood idle or 
disconnected for an appreciable length of time, will cause low mois- 
ture-test results, the amount that the results are low depending upon 
the time that the tester has stood idle. The method for avoiding 
errors from this source is to connect the apparatus, as for use, im- 
mediately after every test is completed, and to make a priming test 
before making a regular test every time new glassware is used or 
when the tester has stood idle for any considerable length of time. 
Table 8. — Failure to make a priming test before the regular test, after the 
machine has been standing idle ivith all connections made, causes a low 
moisture-test result 
Priming 
test made 
by correct 
method 
(per cent 
moisture) 
No priming test made 
Tester 
standing 
2 hours 
(per cent 
moisture) 
Tester 
standing 
5 hours 
(per cent 
moisture) 
Tester 
standing 
20 hours 
(per cent 
moisture) 
Tester 
standing 
40 hours 
(per cent 
moisture) 
16.62 
16.7 
16.4 
0.3 
16.60 
16.7 
16.5 
.2 
-.02 
16.48 
16.7 
16.3 
.4 
-.14 
16.42 
16.5 
16.3 
.2 
-.20 
16.33 
16.5 
16.1 
.4 
-.29 
Table 9. — Failure to make a priming test before the regular test, after the 
machine has been standing open with no connections, causes a low moisture 
result 
Priming 
test made 
by correct 
method 
(per cent 
moisture) 
No priming test made 
Tester 
standing 
1 hour 
(per cent 
moisture) 
Tester 
standing 
3 hours 
(per cent 
moisture) 
Tester 
standing 
6 hours 
(per cent 
moisture) 
Tester 
standing 
20 hours 
(per cent 
moisture) 
Tester 
standing 
40 hours 
(per cent 
moisture) 
10.57 
10.6 
10.5 
.1 
10.50 
10.6 
10.3 
.3 
-.07 
10.50 
10.6 
10.4 
.2 
-.07 
10.38 
10.5 
10.2 
.3 
-.19 
10.33 
10.5 
10.0 
.5 
-.24 
10.15 
10.4 
10.0 
.4 
Average error from correct 
-.42 
$.8% Moisture 
CONNECTIONS 
LEFT 
OPEN 
AND 
NO 
PRIMING 
TEST 
MADE 
TESTER STANDING 
3 HOURS 
TESTER STANDING 
6 HOURS 
TESTER STANDING 
20 HOURS 
TESTER STANDING 
40 HOURS 
ERROR 
-0.075 
% iXjQ. 50% moisture \ 
ERROR 
-0.19% 
ERROR 
-0.24% 
ERROR 
-042% 
10. 33 % moisture , 
10-15% moisture 
9.8% Moisture 
Fig. 25. — Errors resulting from failure to make a priming test before a regular 
test, after the tester has stood idle and disconnected for one hour or longer, 
are here shown 
