a- Length 29.21 cm Width 17.78 cm Height 16.51 cm
b- Length 9.4 cm Width 7.9 cm Height 3.4 cm
c- Length 15.3 cm Width 3.2 cm Height 3.2 cm
d- Length 5.7 cm Width 3.6 cm Height 2.2 cm
e- Length 12.2 cm Width 5.3 cm Height 0.5 cm
f- Length 6.2 cm Width 3.8 cm Height 2.0 cm
g- Length 6.9 cm Width 4.3 cm Height 5.8 cm
h- Length 3.1 cm Diameter 1.8 cm
i- Length 3.4 cm Diameter 1.8 cm
j- Length 3.4 cm Diameter 1.7 cm
k- Length 3.5 cm Diameter 1.7 cm
l- Length 3.8 cm Diameter 1.8 cm
m- Length 3.2 cm Diameter 1.7 cm
n- Length 3.7 cm Diameter 1.9 cm
o- Length 3.7 cm Diameter 1.8 cm
p- Length 3.6 cm Width 2.0 cm Height 1.2 cm
q- Length 2.7 cm Width 1.1 cm Height 0.1 cm
r- Length 2.5 cm Diameter 0.9 cm
s- Length 1.1 cm Diameter 1.0 cm
t- Length 2.7 cm Diameter 0.3 cm
u- Length 13. 9 cm Width 3.8 cm Height 0.5 cm
v- Length 9.6 cm Width 1.9 cm Height 0.3 cm
w- Length 8.5 cm Width 2.4 cm Height 0.3 cm
x- Length 9.6 cm Width 1.9 cm Height 0.3 cm
y- Length 17.8 cm Width 7.5 cm
z-al- Length 17.8 cm Width 7.5 cm
a- A brass instrument for obtaining a diagram of the pressure-volume or pressure-time changes in a steam engine or compression cylinder during the working cycle. The instrument is mounted in a wooden case with a handle. The case is rectangular with brass hinges and internal fittings and hook fastenings. There is an upper compartment and a lower compartment. On the separation between the upper and the lower is a label that reads "DOBBIE MCINNES ENGINE INDICATORS PATENTED AND REGISTERED" and a label on the upper side of the same separation that reads "DOBBIE MCINNES ENGINE INDICATORS PATENTED AND REGISTERED IMPORTANT" (See notes for full label). The indicator is attached to the side of the box. b- A rounded pipe with a nut and washer attached to the to. The number 33 is stamped into both the bottom of the pipe, and the side. A logo has been stamped into the centre. c- A metal rod with threaded ends and 4 nuts of various sizes on each end. d- A metal L shaped handle, with two holes in it, and a screw at the one end. e- A small metal wrench. One side is larger than the other. The larger side is an open end wrench, the smaller a box end wrench. There is a small rectangular hole in the handle, toward the larger side. f- A metal spring with a rounded base and textured metal top. g- A wooden rack for springs. Was originally attached to the box but is now removable. It has six wooden pegs coming up from a wood base that are meant to hold springs. h-o- Eight small metal springs with brass brackets on each end. p- A small metal pulley. It has a small opening at one end of the base. q- A small, flat piece of metal, with three holes punched into it. r- The main body of a small, metal, pill shaped container. s- The lid to the small, metal, pill shaped container. t- The small rod found in the pill shaped container. u- A small triangular piece of wood. It has two lines engraved into it, and a hole between the lines. v- A small wooden ruler, that says "12 TO THE INCH DOBBIE MCINNES". It ranges from 15-0 in increments of 5, and then back from 0-20. w- A small wooden ruler that says "125 TO THE INCH". It goes from 0-350 in increments of 50. x- A small wooden ruler, that says "40 TO THE INCH DOBBIE MCINNES" on it. It ranges from 0-120 in increments of 10. y- A small pad of paper labelled "F 1069 INDICATOR DIAGRAM" (See notes for the full write up). z-al- Small parts from a pad of paper.
Dobbie McInnes Ltd, 57 Bothwell Street, Glasgow. An engine indicator is an instrument for graphically recording the pressure versus piston displacement through an engine stroke cycle. Engineers use the resulting diagram to check the design and performance of the engine.
