CONTENTS.
CHAPTER I.A BRIEF HISTORICAL SKETCH.PAGEEarly Records9Practical beginning of the Art—The London Pneumatic Telegraph10The Siemens Circuit System14Recent Improvements in the London System16An Underground Pneumatic Railway for Transportation of Mail19The Berlin Pneumatic Telegraph20The Paris Pneumatic Telegraph22The Pneumatic Telegraph of other Cities25Pneumatic Tubes in America25CHAPTER II.THE PNEUMATIC TRANSIT COMPANY AND THE FIRST PNEUMATIC TUBES FOR THE TRANSPORTATION OF UNITED STATES MAIL.Organization28Aim and Object of the Company28The Clay-Lieb Patents30Franchises and First Government Contract33Search for Tubes34Method of Manufacturing Tubes35Laying and Opening the Tubes for Traffic37Description of the Tubes, Method of Laying, etc.38The Air-Compressor—Method of Circulating the Air40Terminal Apparatus42The Sender43Sub-Post-Office Receiver44Main Post-Office Receiver47The Carrier50Operation of the Tubes52Benefits of the System54CHAPTER III.THE SYSTEM AND APPARATUS OF THE BATCHELLER PNEUMATIC TUBE COMPANY.General Arrangement and Adaptability of the System57The Size of Tubes64System of very Large Tubes65General Arrangement of Apparatus in the Stations—Two-Station, Two-Compressor Line69Two-Station, One-Compressor Line72Three- to Eight-Station Line74Sending Apparatus79Sending Time-Lock84Intermediate Station Time-Lock88Electro-Pneumatic Circuit-Closer91The Open Receiver94The Closed Receiver99The Intermediate Station Receiving and Transfer Apparatus106Carriers115Air Supply117Fans117Blowers117Air Compressors118The Tube, Line Construction, etc.122CHAPTER IV.FACTS AND GENERAL INFORMATION RELATING TO PNEUMATIC TUBES.Definitions124Intermittent and Constant Air-Current125Laws Governing the Flow of Air in Long Tubes126Law of Pressure128Uses of Pressure Curves130Law of Velocity130Characteristics of the Velocity Curve132Uses of Velocity Curves133Quantity of Air Used134Temperature of the Air135Horse-Power136Efficiency137Pressure and Exhaust Systems138Laws expressed in Mathematical Formulæ141Moisture in the Tubes142Location of Obstructions in Tubes143
A BRIEF HISTORICAL SKETCH.
Early Records
Practical beginning of the Art—The London Pneumatic Telegraph
The Siemens Circuit System
Recent Improvements in the London System
An Underground Pneumatic Railway for Transportation of Mail
The Berlin Pneumatic Telegraph
The Paris Pneumatic Telegraph
The Pneumatic Telegraph of other Cities
Pneumatic Tubes in America
THE PNEUMATIC TRANSIT COMPANY AND THE FIRST PNEUMATIC TUBES FOR THE TRANSPORTATION OF UNITED STATES MAIL.
Organization
Aim and Object of the Company
The Clay-Lieb Patents
Franchises and First Government Contract
Search for Tubes
Method of Manufacturing Tubes
Laying and Opening the Tubes for Traffic
Description of the Tubes, Method of Laying, etc.
The Air-Compressor—Method of Circulating the Air
Terminal Apparatus
The Sender
Sub-Post-Office Receiver
Main Post-Office Receiver
The Carrier
Operation of the Tubes
Benefits of the System
THE SYSTEM AND APPARATUS OF THE BATCHELLER PNEUMATIC TUBE COMPANY.
General Arrangement and Adaptability of the System
The Size of Tubes
System of very Large Tubes
General Arrangement of Apparatus in the Stations—Two-Station, Two-Compressor Line
Two-Station, One-Compressor Line
Three- to Eight-Station Line
Sending Apparatus
Sending Time-Lock
Intermediate Station Time-Lock
Electro-Pneumatic Circuit-Closer
The Open Receiver
The Closed Receiver
The Intermediate Station Receiving and Transfer Apparatus
Carriers
Air Supply
Fans
Blowers
Air Compressors
The Tube, Line Construction, etc.
FACTS AND GENERAL INFORMATION RELATING TO PNEUMATIC TUBES.
Definitions
Intermittent and Constant Air-Current
Laws Governing the Flow of Air in Long Tubes
Law of Pressure
Uses of Pressure Curves
Law of Velocity
Characteristics of the Velocity Curve
Uses of Velocity Curves
Quantity of Air Used
Temperature of the Air
Horse-Power
Efficiency
Pressure and Exhaust Systems
Laws expressed in Mathematical Formulæ
Moisture in the Tubes
Location of Obstructions in Tubes