153 -I
142.0

130.9
120. 1
109.0

97. 5
86.3

65-5

55-2

128.4
118.3
108.3

tl
78.1
68.1
58.0
48.0
37-9

24.7
23.7

22.6
21.9
20.8
IQ.4

18.3
17.7

17-5
17-3

o.i6i
0.167

0.173
0.182
0.191
0.199
0.212
0.234
0.267

0.313

0.839

0.833
0.827
0.818
0.809
0.801
0.788
0.766

0.733
0.687

20
21
22

23
24
25
26

11

29

High-
pressure
cylinder
onlv.
Noi-
condensing,
no  air-pump.
145.9
135-7
125.2

114. 4
103.9

93-0
82.0

71.7
61.6

51-3

128.4
118. 3
108.3
98.2
88.2
78.1
68.1
58.0
48.0
37.9

17.5
17-4
16.9
16.2
15.7
14.9
13  9

13.6
13.4

0.120
0.129

0.135
0.142
0.152
0.160
0.170
0.191
0.221
0.262

0.880
0.871
0.865
0.858
0.848
0.840
0.830
0.809
0.779
0.738

The  engine  during  the  experiments  made  58  revolutions  per
minute.    The  air-pump  had  two  single-acting  vertical  pistons.
Each  experiment  lasted  10  or  20  minutes,  during  which  the
load  on  the  brake  was  maintained  constant,  and  indicator-
diagrams  were  taken.    The  experiments  with  small  load  on  the


INITIAL  FRICTION   AND   LOAD   FRICTION


289


brake  (numbers  9,  18,  19,  28,  and  29)  were  irregular  and  uncer-
tain.
The  first  nine  tests  were  made  with  the  engine  working  com-
pound. Tests  10  to  19  were  made  with  the  high-pressure  cylin-
der only  in  action  and  with  condensation,  the  low-pressure  con-
necting-rod being  disconnected.  Tests  20  to  29  were  made  with
the  high-pressure  cylinder  in  action,  without  condensation.
The  results    of  these  tests  are  plotted  on  Fig.  60,  using  the


ABSCiaaAE,   EFFCCnVI  HORSEPOWBI.
ohdinates,  fwction  »iorsepower.
2L


Fig.  60.
