

Page 
Chapter 1.  
General Principles 
7 


Fundamental Characteristics 
7 
Elementary Optical Principles 
11 


Chapter 2.  
Geometrical Principles of Rangefinding 
26 

The Arithmetic and Graphic Analyses of Range Cuts 
31 


Chapter 3.  
Geometrical and Optical Principles as applied to the Rangefinder 
43 

Fundamental Arrangement 
43 
Action of the Deflecting Prisms 
46 
Attitude of Images as affected by the Optical Parts 
46 
The Functions of the various Parts of the Rangefinder 
49 

Separation of the Upper Field from the Lower 
49 
Combined Effect of the End Reflector and the Objective 
51 
Effect of the Equal Magnification Lens 
53 
Effects of the Halving Glass and Deflecting Prism on the attitude of the Image 
53 
Combined Effects of the Eyepiece Prisms 
53 
The Eyepiece Lenses 
65 
The Finder 
76 
The Astigmatiser 
83 
The Range Working Head, Deflecting Prisms, and Scale Gear 
88 
The Coincidence Adjustment Gear 
99 
The Halving Adjustment Gear 
107 
The Frame Supports 
120 
The Infinity Adjuster 
124 
The Uniform Range Scale AutoTransmission Gear 
128 
The Hand Following Mechanism 
131 


Chapter 4.  
Instructions as tp the Use and Care of the Rangefinders 
133 

Selection and Training of Rangetakers 
133 
The Operation of RangeTaking 
136 
The Correction of Halving Errors 
139 
The Correction of Coincidence Errors 
140 
Instructions for Dismantling the Various Rangefinders 
144 
The Care of Rangefinders 
149 
Abnormal Errors and their Correction 
151 

Chapter 5.  
Tables of Approximate Uncertainty of Observation 
156 


Standard Types of Rangefinders, with Scale Data 
157 
Approximate Uncertainty of Observation 
157 


Chapter 6.  
Types of Mountings in the Naval Service with the various Rangefinders 
160 

Description of the Mountings in Naval Service 
160 
Belt and Rail Mounting, Type M.B. 4 
160 
Belt Mounting, Type M.B. 7 
161 
Rail Mounting, Type M.E. 3 
161 
Rail Mounting, Type M.E. 6 
161 
Turret Mounting, Type M.G. 3 
161 
Turret Mounting, Type M.G. 8 
162 
Turret Mounting, Type M.G. 11 
163 
Tripod Mounting, Type M.H. 28 
163 
Tripod Mounting, Type M.H. 37 
164 
Traversing Mounting, Type M.J. 1 
164 
Traversing Mounting, Type M.J. 2 
165 
Turret Mountings, Types M.L. 10, M.L. 11, and M.L. 12 
165 
Turret Mounting, Type M.L. 13 
165 
Fixed Mounting, Type M.N. 1 
165 
Fixed Mounting, Type M.N. 2 
166 
Traversing Mounting, Type M.P. 2 
166 
Traversing Mounting, Type M.P. 3 
167 
Fixed Mounting, Type M.Q. 1 
167 
Fixed Mounting, Type M.Q. 10 
168 
High Angle Mounting, Type M.T. 3 
168 
High Angle Mounting, Type M.T. 4 
168 
High Angle Mounting, Type M.T. 6 
169 
Gun Control Tower Mounting, Type M.W. 1 
170 