Features
Light and Vision--More Especially How Light is Converted Into Thought
Experiments on the Head of a Guillotined Patient
A Trip Over the Central Pacific Railroad
Boring Insects
Improved Packing Steam Drying Cylinders on Paper Machines
Submerged Buoys as a Basis for Structures in Deep Water
Editorial Summary- April 23, 1970
Kay's Patent Reversible Slide Valve and Swing Grate
Stockwell's Improved Combination Tool
Steam Boiler Inspection
An Anglo-American Turkish Bath
Principle of the Lever
The Paris Observatory
Shut Your Mouth
The West Side Elevated Railway
Comparison of Turbines with other Water Wheels
Where and How Corks are Cut
Recent American and Foreign Patents- April 23, 1870
Answers to Correspondents- April 23, 1870
United States Supreme Court
Official List of Patents- April 23, 1870
H. S. Patent Office- April 23, 1870
Departments
- Letters
Correspondence- April 23, 1970
- Recommended
New Books and Publications- April 23, 1970
- Departments
Business and Personal- April 23, 1870
