158 Sir George Shuckburgh Evelyn's Endeavours 
(§. 2 6.) The bar was then placed in the rectangular gauge 
klmn, fig. 2. in the direction p 0 ; and the end of the micro™ 
, meter screw brought to bear against it repeatedly, so as to 
touch without force, or considerable pressure; and the divi- 
sions* cut by the index, on the micrometer plate of the gauge, 
were as follow : 
Trial ist. 
Division on the 
micrometer. 
% 
63 
66 
70 
66 
Trial 2d. 
Division on the 
micrometer. 
— ■ 
therm. 
"62°, 0 
64 1 
6 2 
% 
6a 
therm. 
^62°,© 
64D 
65 
66' > 
63 
6‘2T 
0 
62 \ 
6 3,3 + 
64,2 
Trial 3d. 
Division on the 
micrometer. 
thermom. 
6 2 0 , 3 
Mean = 66 
The mean of these three means is 64,5, with the temperature 
62°, 1. 
(§. 27.) The bar was now removed from the gauge, and 
the sphere put there in its place ; and, by means of the three 
great circles, each of which was divided into 8 equal parts, nine 
several diameters of the sphere were taken, as follow : 
Div. of 
microm. 
AB 
Mean=45 
Div. of 
microm. 
f4°' 
'4°' 
1 5° 
.therm. 
^ 62 0 t 
diam. 
42 
• 
147 
GH ' 
45 ^ 
42 
2 
42 
. 46 . 
.44j 
therm. 
6 2°, 5 
4 2 > 6 
Div. of 
microm. 
r 
S4 1 
diam. I 4 ^ 
CD I 43 
42 
.Hi 
therm’ 
£>2°, 4 
1 
J 
43>9 
Div. of 
microm. 
f 44 j 
diam. J 4 . therm. 
IK 1f>2°,5 
451 
.46J 
4 5 $ 
* Each thread of this screw is — r | T inch, and each revolution of the screw is di- 
vided into 100 ; so that every division on the micrometer plate is — T ~ 55 inch. 
f In all these experiments with the gauge, the figures on the micrometer plate in- 
crease as the screw goes forward ; viz . the higher numbers indicate a less interval 
or diameter. 
