The Caisson for the East Pier of the St. Louis Bridge

The Patent Laws

Triangular Suspension Bridge

The Ivory Plant

Boring for Oil

Improved Power Hoisting Machine

Instruments used in Storm Signal Service

Furrowing Hammer for Stone Dressing

Iron Rails for Common Roadways

Firing of Steam Boilers

Pisciculture in New York and New Jersey

Artificial Stone

Employment of Females in New York

Suggestions for the Improvement of Railways

The Battle of the Tires

Scientific Intelligence- April 15, 1871

Queries- April 15, 1871

Answers to Correspondents- April 15, 1871

Recent American and Foreign Patents- April 15, 1871

Official List of Patents- April 15, 1871

Issued by the U. S. Patent Office

Applications for Extension of Patents- April 15, 1871