Features
The Arches of Mexico
Relics of Early Spanish Engineering
Battleship Drill Indoors
How New York Trains Her Naval Militia
The Reflector--The Telescope of the Future
Why the Large Refractor Must Give Way to Mirrors
Carrier Pigeons in the French Army
Curious Resemblances in Nature
A Clock That Speaks the Time of Day
A Mercury Interruptor
A Seconds Pendulum
German Inventors and Office Furniture, The International Cone of Zoology
The Industrial Need of Technically Trained Men--V
A Variety of Avenues Open to the Young Man of To-day
Departments
- Letters
Correspondence - July 12, 1913
- Recommended
New Books, Etc. - July 12, 1913
- Departments
Inventions New and Interesting - July 12, 1913
Recently Patented Inventions - July 12, 1913
Notes and Queries - July 12, 1913
