364 
VELOCITY AND PRESSURE INSTRUMENTS. 
with those previously taken, which will be the case if the disjunctor is 
correct. 
If there should be any difference between the height of these two series, it 
represents double the error of the disjunctor, and from the relative position of 
the marks it can be seen on which side contact is first broken— i.e. } which 
plate is raised before the other. To correct this error, it is only necessary 
to elevate or lower one of the screws, v v r , until both plates are raised by the 
cross-piece of the spring exactly at the same instant. 
6. Comparison with the Navez-Leurs and other Instruments. 
The following table gives the results of a comparative trial of the 
Le Boulenge and Navez-Leurs chronographs. The instruments were both 
introduced into one and the same circuit through the screens, so that the 
velocity of each shot was simultaneously recorded on each of them. 
Table of Comparison between the Navez-Leurs and the Le Boulenge Chronographs, 
Nature of 
powder 
and charge. 
Velocity 
by 
Navez- 
Leurs 
at 105 ft. 
Velocity 
by Le 
Boulengd 
at 105 ft. 
i 
5® 
a 
p 
Nature of 
powder 
and charge. 
Velocity 
by 
Navez- 
Leurs 
at 105 ft. 
Velocity 
by Le 
Boulenge 
at 105 ft. 
§ 
3 
M 
% 
p 
r 
951 
950 
+ 1 
r 
1009 
1004 
+ 5 
933 
927 
+ 6 
1003 
996 
+ 7 
g 
943 
938 
+ 5 
a 
998 
993 
+ 5 
942 
938 
+ 4 
3 
&J0 
99S 
993 
+ 5 
962 
959 
+ 3 
P 
1005 
1001 
+ 4 
i4 
985 
981 
+ 4 
1020 
1014 
+ 6 
P 
983 
977 
+ 6 
h4 
1019 
1015 
+ 4 
F=i 
998 
992 
+ 6 
1021 
1019 
+ 2 
u 
pH 
983 
978 
+ 6 
993 
988 
+ 5 
ci 
988 
986 
+ 2 
Ph 
998 
993 
+ 5 
1—1 
979 
975 
+ 4 
I—1 
1018 
1013 
+ 5 
a 
o 
973 
970 
+ 3 
g 
1020 
1018 
+ 2 
Cm 
976 
980 
- 4 
£ 
1017 
1013 
+ 4 
TS 
© 
993 
989 
+ 4 
1017 
1014 
+ 3 
crt 
987 
985 
+ 2 
CD 
992 
987 
+ 5 
r 
982 
979 
+ 3 
ed 
990 
986 
+ 4 
990 
988 
+ 2 
m 
993 
988 
+ 6 
993 
995 
- 2 
03 
989 
983 
+ 6 
43 
998 
1001 
- 3 
rH 
1009 
1006 
+ 3 
£ 
986 
990 
- 4 
*4^ 
2 / 
1003 
997 
+ 6 
go 
965 
963 
+ 2 
m 
1006 
1001 
+ 5 
962 
959 
+ 3 
1003 
999 
+ 4 
972 
971 
+ 1 
rO 
993 
989 
+ 4 
r-1 
961 
958 
+ 3 
rH 
998 
993 
+ 5 
§0 
951 
950 
+ 1 
go 
991 
985 
+ 6 
§ 
987 
986 
+ 1 
998 
995 
+ 3 
6 
1023 
1019 
+ 4 
A 
1006 
1003 
+ 3 
1017 
1013 
+ 4 
o 
1001 
997 
+ 4 
1023 
1020 
+ 3 
1002 
999 
+ 3 
u 
1005 
1001 
+ 4 
< 
1002 
999 
+ 3 
1008 
1004 
+ 4 
& 
991 
992 
- 1 
© 
998 
991 
+ 7 
if 
995 
994 
+ 1 
£ 
1008 
1002 
+ 6 
© 
980 
977 
+ 3 
o 
1008 
1003 
+ 5 
1 
977 
978 
- 1 
Ph 
1015 
1008 
+ 7 
Ph 
983 • 
979 
+ 4 
6 
1021 
1016 
+ 5 
cb 
981 
979 
+ 2 
1-4 
1017 
1012 
+ 6 
h4 
998 
996 
+ 2 
p4 
1019 
1016 
+ 4 
p4 
990 
990 
0 
1003 
999 
+ 4 
996 
995 
+ 1 
- 
1008 
1006 
-f 2 
989 
988 
+ 1 
